Multiplying two 2 digit numbers difference of 1
1.Choose a 2-digit number.
2.Select a number either 1 smaller or 1 larger.
3.Square the larger number (multiply it by itself).
4.Subtract the larger number from the product.OR
5.Square the smaller number (multiply it by itself).
6.Add the smaller number to the product. Pick the easier one to square.
1.If the first number is 76, choose 75 as the second number.
See the pattern?
2.75 x 75 = 5625 (square the smaller). Remember how to square a two-digit number ending in 5?
3.5625 + 75 = 5700 (add the smaller).
4.So 76 x 75 = 5700.
1.If the first number is 32, choose 31 as the second number.
2.32 x 32 = 1024 (square the larger). Remember how to square a two-digit number ending in 2?
3.1024 - 32 = 992 (subtract the larger).
4.So 32 x 31 = 992.
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