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Missing Digit

8 questions · EasyMedium

Missing-digit questions hide one digit of a sum or difference. Work column by column from the right, keeping track of carries.

💡 Quick tricks

Find the hidden digit by doing the inverse operation: in A + B = C, A = C − B.
Check the units column first: it often gives the answer straight away.
Confirm by putting the digit back and redoing the full sum.

8 questions

🎯 Try it yourself

Tap an answer. You'll see if it's right, and why. Easy ones come first.

Q1Easy

39□ + 391 = 781. Find □.
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Answer: D. 0
💡 390 + 391 = 781, so □ = 0.
Q2Easy

36□ + 363 = 730. Find □.
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Answer: A. 7
💡 367 + 363 = 730, so □ = 7.
Q3Easy

8□9 + 141 = 970. Find □.
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Answer: D. 2
💡 829 + 141 = 970, so □ = 2.
Q4Easy

68□ + 172 = 854. Find □.
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Answer: A. 2
💡 682 + 172 = 854, so □ = 2.

Q5Medium

7□3 − 579 = 204. Find □.
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Answer: A. 8
💡 783 − 579 = 204, so □ = 8.
Q6Medium

1□56 − 666 = 890. Find □.
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Answer: A. 5
💡 1556 − 666 = 890, so □ = 5.
Q7Medium

1□33 − 736 = 497. Find □.
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Answer: C. 2
💡 1233 − 736 = 497, so □ = 2.
Q8Medium

6□9 − 204 = 435. Find □.
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Answer: B. 3
💡 639 − 204 = 435, so □ = 3.

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