Step-by-step Maths Level 4: Counting in hundreds
Part of the Step-by-step Maths Level 4 counting and place value to 10000 chapter. Chapter overview · whole chapter on one page
Counting in hundreds
Counting in hundreds means each number is 100 more than the one before. Only the hundreds digit goes up by 1 each time, until the hundreds go past 9. Then the thousands digit goes up by 1.
Counting back in hundreds means each number is 100 less than the one before.
Key ideas
- Counting on in hundreds adds 100 each time.
- Counting back in hundreds takes away 100 each time.
- Find the step first, then count in that step.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.2350
- Add 100 each time. Each count moves by the same step.2350 + 100 = 2450
- Add 100 each time. Each count moves by the same step.2450 + 100 = 2550
- Add 100 each time. Each count moves by the same step.2550 + 100 = 2650
- Write the answer. This is the last number we reached.2650
Check. Count the steps back: 2650 - 300 = 2350.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.4100
- Take 100 each time. Each count moves by the same step.4100 - 100 = 4000
- Take 100 each time. Each count moves by the same step.4000 - 100 = 3900
- Write the answer. This is the last number we reached.3900
Check. Count the steps back: 3900 + 200 = 4100.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Find the step between the numbers, then count on to fill the gap.
- Find the step. The numbers go up by the same amount each time.6300 - 6200 = 100
- Count on from 6300. Add the step to the number before the gap.6300 + 100 = 6400
- Write the missing number. It fits the pattern.6400
Check. Check: 6400 + 100 = 6500, the next number.
Watch out. Look at the numbers either side of the gap.
Watch out
Watch out. 2950 + 100 is 3050, not 2960. The hundreds go past 9, so the thousands digit goes up.
Exam tip
Grown-up tip. Ask the child to say the step out loud as they go: “2350, 2450, 2550.” Aim to count in hundreds from any number in under 10 seconds.
Exercise 1A Practice: counting in hundreds
Non-calculatorMethod. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.3009
- Add 100 each time. Each count moves by the same step.3009 + 100 = 3109
- Add 100 each time. Each count moves by the same step.3109 + 100 = 3209
- Add 100 each time. Each count moves by the same step.3209 + 100 = 3309
- Add 100 each time. Each count moves by the same step.3309 + 100 = 3409
- Add 100 each time. Each count moves by the same step.3409 + 100 = 3509
- Write the answer. This is the last number we reached.3509
Check. Count the steps back: 3509 - 500 = 3009.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.1290
- Take 100 each time. Each count moves by the same step.1290 - 100 = 1190
- Take 100 each time. Each count moves by the same step.1190 - 100 = 1090
- Write the answer. This is the last number we reached.1090
Check. Count the steps back: 1090 + 200 = 1290.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.2082
- Add 100 each time. Each count moves by the same step.2082 + 100 = 2182
- Add 100 each time. Each count moves by the same step.2182 + 100 = 2282
- Add 100 each time. Each count moves by the same step.2282 + 100 = 2382
- Add 100 each time. Each count moves by the same step.2382 + 100 = 2482
- Add 100 each time. Each count moves by the same step.2482 + 100 = 2582
- Write the answer. This is the last number we reached.2582
Check. Count the steps back: 2582 - 500 = 2082.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.1910
- Take 100 each time. Each count moves by the same step.1910 - 100 = 1810
- Take 100 each time. Each count moves by the same step.1810 - 100 = 1710
- Take 100 each time. Each count moves by the same step.1710 - 100 = 1610
- Take 100 each time. Each count moves by the same step.1610 - 100 = 1510
- Write the answer. This is the last number we reached.1510
Check. Count the steps back: 1510 + 400 = 1910.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.1478
- Add 100 each time. Each count moves by the same step.1478 + 100 = 1578
- Add 100 each time. Each count moves by the same step.1578 + 100 = 1678
- Add 100 each time. Each count moves by the same step.1678 + 100 = 1778
- Add 100 each time. Each count moves by the same step.1778 + 100 = 1878
- Write the answer. This is the last number we reached.1878
Check. Count the steps back: 1878 - 400 = 1478.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.7174
- Add 100 each time. Each count moves by the same step.7174 + 100 = 7274
- Add 100 each time. Each count moves by the same step.7274 + 100 = 7374
- Add 100 each time. Each count moves by the same step.7374 + 100 = 7474
- Write the answer. This is the last number we reached.7474
Check. Count the steps back: 7474 - 300 = 7174.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.8726
- Add 100 each time. Each count moves by the same step.8726 + 100 = 8826
- Add 100 each time. Each count moves by the same step.8826 + 100 = 8926
- Add 100 each time. Each count moves by the same step.8926 + 100 = 9026
- Add 100 each time. Each count moves by the same step.9026 + 100 = 9126
- Add 100 each time. Each count moves by the same step.9126 + 100 = 9226
- Write the answer. This is the last number we reached.9226
Check. Count the steps back: 9226 - 500 = 8726.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Find the step between the numbers, then count on to fill the gap.
- Find the step size from two numbers that are next to each other. The step is the same all the way along.5164 - 5064 = 100
- Count from the number before the gap. Add the step to get the missing number.4964 + 100 = 5064
- Write the missing number. It fits the pattern.5064
Check. Check: 5064 + 100 is the next number, 5164.
Watch out. Look at the numbers either side of the gap. The step is the same each time.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.7878
- Add 100 each time. Each count moves by the same step.7878 + 100 = 7978
- Add 100 each time. Each count moves by the same step.7978 + 100 = 8078
- Add 100 each time. Each count moves by the same step.8078 + 100 = 8178
- Add 100 each time. Each count moves by the same step.8178 + 100 = 8278
- Add 100 each time. Each count moves by the same step.8278 + 100 = 8378
- Write the answer. This is the last number we reached.8378
Check. Count the steps back: 8378 - 500 = 7878.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.7424
- Take 100 each time. Each count moves by the same step.7424 - 100 = 7324
- Take 100 each time. Each count moves by the same step.7324 - 100 = 7224
- Take 100 each time. Each count moves by the same step.7224 - 100 = 7124
- Take 100 each time. Each count moves by the same step.7124 - 100 = 7024
- Take 100 each time. Each count moves by the same step.7024 - 100 = 6924
- Write the answer. This is the last number we reached.6924
Check. Count the steps back: 6924 + 500 = 7424.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.9961
- Take 100 each time. Each count moves by the same step.9961 - 100 = 9861
- Take 100 each time. Each count moves by the same step.9861 - 100 = 9761
- Take 100 each time. Each count moves by the same step.9761 - 100 = 9661
- Write the answer. This is the last number we reached.9661
Check. Count the steps back: 9661 + 300 = 9961.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.4069
- Take 100 each time. Each count moves by the same step.4069 - 100 = 3969
- Take 100 each time. Each count moves by the same step.3969 - 100 = 3869
- Write the answer. This is the last number we reached.3869
Check. Count the steps back: 3869 + 200 = 4069.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.8581
- Add 100 each time. Each count moves by the same step.8581 + 100 = 8681
- Add 100 each time. Each count moves by the same step.8681 + 100 = 8781
- Add 100 each time. Each count moves by the same step.8781 + 100 = 8881
- Add 100 each time. Each count moves by the same step.8881 + 100 = 8981
- Add 100 each time. Each count moves by the same step.8981 + 100 = 9081
- Write the answer. This is the last number we reached.9081
Check. Count the steps back: 9081 - 500 = 8581.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Find the step between the numbers, then count on to fill the gap.
- Find the step size from two numbers that are next to each other. The step is the same all the way along.4871 - 4771 = 100
- Count from the number before the gap. Add the step to get the missing number.4771 + 100 = 4871
- Write the missing number. It fits the pattern.4871
Check. Check: 4871 + 100 is the next number, 4971.
Watch out. Look at the numbers either side of the gap. The step is the same each time.
Method. Count in steps of the same size, one step at a time.
- Start at the first number. It is where we begin.4363
- Take 100 each time. Each count moves by the same step.4363 - 100 = 4263
- Take 100 each time. Each count moves by the same step.4263 - 100 = 4163
- Write the answer. This is the last number we reached.4163
Check. Count the steps back: 4163 + 200 = 4363.
Watch out. Each step adds or takes away the same amount. Do not start counting again from the beginning.
Method. Find the step between the numbers, then count on to fill the gap.
- Find the step size from two numbers that are next to each other. The step is the same all the way along.7233 - 7133 = 100
- Count from the number before the gap. Add the step to get the missing number.7133 + 100 = 7233
- Write the missing number. It fits the pattern.7233
Check. Check: 7233 + 100 is the next number, 7333.
Watch out. Look at the numbers either side of the gap. The step is the same each time.