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34. a) 15 x 6
b) 5 x 6 + 36 + 42 + 48 + 54
= 5 x 6 + 6 x 6 + 6 x 7 + 6 x 8 + 6 x 9
= 6 x (5 + 6 + 7 + 8 + 9)
= 6 x 35
c) 5 x 7 + 20 + 22 + 14
= 5 x 7 + 5 x 4 + 22 + 14
= 5 x ( 7 + 4 ) + 22 + 14
= 5 x 11 + 2 x 11 + 14
= 11 x (5 + 2) + 14
= 11 x 7 + 2 x 7
= 7 X (11 + 2)
= 7 X 13
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