Given that:
5x+10y=460 --> 10y=460-5x;
x>y --> 10x>10y.

10x>460-5x --> 15x>460 --> x>30.something --> x=32.

Answer: A.
_________________

hmm, never struck me to use plugging in while solving it algebraically.

If she had an equal number of each, , she could have 30 of each for a total of $450, and another 2 fivers to make $460. TOTAL = 32. Note that all other choices would give less than $450.

OK so there is a 2:1 ratio between 5 and 10 dollar notes. This means that the answer choice can only be even.
so that's A, B or D.

Test b: number of 5 dollar notes equal 30. total revenue=150. To make up to 460 total, you need 31 ten dollar notes.
Since there is a greater number of $10 dollar notes than $5 dollar notes. Requirement not met.
We also know that D is wrong now...as it would give more $10 dollar notes than $5. Therefore A must be the right choice.

We can create the following equation in which f = the number of 5-dollar bills and t = the number of 10-dollar bills.

5f + 10t = 460

f + 2t = 92

If the number of 5-dollar bills and the number of 10-dollar bills are equal, i.e., f = t, then we have:

f + 2f = 92

3f = 92

f = 30⅔

Since f, the number of 5-dollar bills, must be a whole number, and f > t, f should be at least 31. Let’s check whether f can be 31t:

If f = 31, then 31 + 2t = 92 → 2t = 61 → t = 30.5. However, t must be whole number also, so f can’t be 31.

Now let’s check if f can be 32:

If f = 32, then 32 + 2t = 92 → 2t = 60 → t = 30. We see that t is a whole number and f > t. So, the least possible value of f is 32.

Answer: A
_________________