Question 1112387
The length is 85 and the ratio is 2:3:5. Now, 2+3+5 = 10, which means that in every group of 10 there are 2 of one, 3 of another, and 5 of yet another.
How many groups of 10 go into 85? Well, 85/10 = 8.5. Aha! We've got our answer:
(2 x 8.5) + (3 x 8.5) + (5 x 8.5) = 85 let's see if this is true:
17 + 25.5 + 42.5 = 85 Correct
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An alloy consist of steel silver and copper in the ratio of 6:5:9 . the smallest mass (silver) is 160 grams. So 5 = 160
IF:
5 = 160 
then: 
(160*6)/5 = 192
(160*9)/5 = 2886 x 160)/5 = 288
mass of silver: 160
mass of steel: 192
mass of copper: 288
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The mass of copper in the alloy is 289
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