GMATPrep 2 PS questions

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GMATPrep 2 PS questions

by aimhigh715 » Thu Nov 29, 2007 7:27 pm
Thanks in advance!
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by Suyog » Thu Nov 29, 2007 9:55 pm
1. Since 14 and 35 are the factors of some number, the number has to be multiple of 70 and hence everytime the unit digit will be 0, SUFF

2. unit digit of 2^5 - 2
unit digit of 3^2 - 9
unit digit of 5^7 - 5
unit digit of 7^6 - 9, multiplying these numbers also gives 0 as unit digit, SUFF

Ans D