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Specific Tricks

Level 16 / build-up

Add via sub (2d + near-round)

3 visual steps / add near round

1. Use round

47 + 991. Use roundAdd the nearby round number.147 + 100 = 1472remove 13answer 146
Add the nearby round number.

Add the nearby round number.

2. Remove extra

47 + 992. Remove extraSubtract the extra amount.147 + 100 = 1472remove 13answer 146
Subtract the extra amount.

Subtract the extra amount.

3. Final answer

47 + 993. Final answerKeep the adjusted total. Read answer answer 146Keep the adjusted total.
Keep the adjusted total.

Keep the adjusted total.

Practice Level 16

Name the shape first; the shortcut stays small.

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