The only contents of a parcel are 25 photographs and 30 negatives. What is the total weight, in ounces, of the parcel's contents?
(1) The weight of each photograph is 3 times the weight of each negative.
(2) The total weight of 1 of the photographs and 2 of the negatives is i ounce.
Sol: let the weight of 1 photograph be a ounce and that of negatives be b ounce so we need to find 25a+30b
St1 says a=3b is not enough cause weight of negative can be anything so not sufficient. Ans choice A &D ruled out
St2 says a+2b=1 ounce. It's difficult to get individual values
On combining we get a=3b and a+2b=1
We can solve for a and b
So ans is C
Just for information cause we need not find values
5b=1 so b=1/5 ounce and a=1/15 ounce
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