MENTAL ARITHMETIC: MULTIPLICATION PROBLEMS (2) The distributive property To see the answer, pass your mouse over the colored area. 13. Calculate in writing by distributing the multiplier to each unit of the
13. a) 3 × 42 13. b) 5 × 34 = 5 × 30 + 5 × 4 = 150 + 20 = 170 13. c) 6 × 32 = 6 × 30 + 6 × 2 =180 + 12 = 192 13. d) 7 × 56 = 350 + 42 = 392 13. e) 8 × 97 = 720 + 56 = 776 13. f) 2 × 346 = 600 + 80 + 12 = 692 13. g) 3 × 475 = 1200 + 210 + 15 = 1425 13. h) 7 × 908 = 6300 + 56 = 6,356 13. i) 9 × 4,005 = 36,000 + 45 = 36,045 13. j) 6 × 7.30 = 42 + 1.80 = 43.80 13. k) 9 × 4.50 = 36 + 4.50 = 40.50 14. Whatever you wrote in the previous problem, do mentally here.
15. Calculate each column mentally.
16. You have 47 twenty-dollar bills. Calculate mentally how much 2 × 47 = 80 + 14 = 94. Therefore 20 × 47 = $940. 17. Multiply each column mentally. These are dollars and cents.
18. Multiply each column mentally by distributing the multiplier to the
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