Mult Nums Less 100

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(*) Multiplying Two Numbers Less Than 100, But Close To 100:

   A. From algebra we learn:

(100 a) (100 b) = 100((100 a) b) + ab

   B.  Using numbers instead of variables we get the following:

1.  Find the difference between both of the numbers and 100.

2.  Multiply these two values together and write it down.  Make sure the answer takes up 2 place values.

3.  Subtract the difference found in step 1 of one of the numbers with the remaining number.  Write the result.

Ex [1]  98 x 97 =_________.

a)      100 98 = 2.

b)      100 97 = 3.

c)      2 x 3 = 6.  Write 06 to take up 2 place values.

d)      98 3 = 95.  Write 95.  (You can also use 97 2 = 95)

e)      The answer is 9506.

Ex [2]  88 x 93 =_________.

a)      100 88 = 12.

b)      100 93 = 7.

c)      12 x 7 = 84.  Write 84.

d)      93 12 = 81.  Write 81.  (You can also use 88 7 = 81)

e)      The answer is 8184.

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