Three friends contributed some funds for a party. What was the amount

Let the three friends be A,B and C.
Lets assume the contribution of A - x$,the contribution of B - y$ and the contribution of C - z$
Total = x + y + z

1. The total funds collected were $510.
x +y + z = 510 = Total
But since we do not know what the split in which they contribute,
we cannot clearly who made the the highest contribution,
and what the contribution was.(Insufficient)

2. Had each friend contributed $10 extra, the ratio of their contributions would have been 2 : 3 : 4.
Without knowing the initial total, we cannot clearly tell what the highest contribution was.
If x=10,y=20,z=30, after adding 10$ to each of their contributions, we have the ratio 2:3:4
Similarly, if x=40,y=65,z=90 also we will get the same ratio (Insufficient)

On combining the information, the initial amount must have been 110,170 and 230(totaling 510),
after adding to which we will get 120,180,240(Ratio - 2:3:4) (Sufficient) (Option C)

Statement 1 allows you to calculate the average (170) so that isn't sufficient

For statement 2 it is easy to see that 10, 20, 30 satisfies statement however, if you are struggling to find another set of numbers, you can instead cheat and utilize the first statement which implies that 10,20, & 30 are not the only amounts that can satisfy the ratio.

Three friends contributed some funds for a party. What was the amount contributed by the friend who contributed the highest amount?

(1) The total funds collected were $510.
(2) Had each friend contributed $10 extra, the ratio of their contributions would have been 2 : 3 : 4.

Solution:

Statement : We can't find the highest contribution made . x+y+z=510. Insufficient.

Statement 2: x+10:y+10:z+10=2:3:4. Insufficient on its own.

Combining both the statements, we get x+y+z+30=510.
9x=540. We get the highest amount contributed to be 240.

Therefore the answer is Option C.

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