At first: ratio 3 : 1, difference = 2
After: ratio 6 : 1 difference = 5
Since the difference in price between the bear and clowns are the same, we make the ratio so that the difference is the same. So we multiply the first ratio by 5 and the second ratio by 2. i.e.
At first: 15 : 5 difference = 10
after: 12 : 2, difference = 10.
we see that 3 units = $12.
so 1 unit = $4
Bear before sale = 15 units = 15 * 4 = $60