Take-Away Turtles
8431 − 2567
8431 − 2567 = 5864
What place value is the 2 in? In the number 54,726
Tens
4123 − 1987
=2,136
Solve: 8431 − 2567
=5,864
Create a subtraction problem that results in 1,111 as the answer. Use two 4-digit whole numbers
2,222 − 1,111 = 1,111; 5,555 − 4,444 = 1,111.
7020 − 3895
7020 − 3895 = 3125
What place value is the 6 in? In this number? 678,987
Hundred Thousands
7510 − 2649
=4,861
What is 4,382 − 30? Explain how subtracting 30 affects each digit and why regrouping might or might not be needed.
Subtracting 30 decreases the tens by 3; no regrouping needed because tens digit 8 ≥ 3.
Mia says that 6,000 − 2,478 = 3,522 because she subtracted 2 from 6 and then 478 from 0. Explain why Mia’s method is incorrect, show a correct place-value subtraction using borrowing, and give the correct answer.
6,000 − 2,478 = 3,522
9005 − 4789
9005 − 4789 = 4216
What place value do you start with when subtracting?
The ones
8264 − 4398
=3,866
Start with 6,045. Subtract 300. Show the subtraction using place-value reasoning (words and numbers). Do you need to regroup? Why or why not?
6,045 − 300 = 5,745. Subtracting 300 decreases the hundreds by 3; regrouping not needed because hundreds digit 0 < 3? (Teacher note: show borrowing from thousands: 6 thousands → 5 thousands and hundreds become 10 → 10−3=7; result 5,745.)
A student claims: “If I subtract 1,000 from any 4-digit number, only the thousands digit changes.” Is this always true? Provide two example numbers that show when it is true without regrouping and when it requires regrouping (explain both).
4,500 − 1,000 = 3,500 (no regrouping); 3,005 − 1,000 = 2,005 (no regrouping still) — provide one requiring borrow? (Subtracting 1,000 never requires borrowing
6342 − 2987
6342 − 2987 = 3355
What number is this 60,000+4,000+700+40+6
64,746
9001 − 4675
Solve 7,321 −4,876 by decomposing each number into thousands, hundreds, tens, and ones (write each step: thousands difference, hundreds difference, etc.) Then combine the results.
7,321 − 4,876: thousands: 7−4=3; hundreds: 3−8 (need to borrow → borrow 1 thousand → hundreds 13−8=5); tens: borrow made tens 2 becomes 1? (Combine carefully) Final result = 2,445. (Students should show borrowing steps.)
Design a real-world word problem involving money that requires a 4-digit subtraction with multiple regroupings (at least two borrows). Write the problem, then solve it using place-value steps and explain each borrow.
examples:student budget $9,437, spent $4,689 and $2,953 on two trips; remaining = 9,437 − (4,689 + 2,953) solved by subtracting sums with borrows.
5000-1876
5000 − 1876 = 3124
What number is this? 900,000+90,000+7,000+600+20+1
997,621
10000 − 3748
A student says 5,000 − 1,876 = 4,124. Is the student correct? Explain using place-value thinking and correct the work if needed.
The student who said 4,124 is incorrect. Use place-value subtraction: 5,000 − 1,876 = 3,124 (show borrowing from thousands into hundreds, tens, ones).
Without performing full subtraction, determine whether each subtraction below will require regrouping (yes/no) and briefly justify:
a) 5,200 − 1,379
b) 6,403 − 2,608
c) 7,010 − 3,995
d) 4,560 − 2,451
a) yes; b) yes; c) yes; d) no.