a) Select a variety of one- and two-digit numbers between
Chapter 1, Problem 1.1.30(choose chapter or problem)
a) Select a variety of one- and two-digit numbers between 1 and 99 and multiply each by 9. Record your results. b) Find the sum of the digits in each of your products in part (a). If the sum is not a one-digit number, find the sum of the digits again until you obtain a one-digit number. c) Make a conjecture about the sum of the digits when a oneor two-digit number is multiplied by 9.
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