we have 24= 2^3 x 3 ; 30=2 x 3 x 5 ; 36= 2^2 x 3^2
so lcm of 24, 30, 36 is 2^3 x 5 x 3^2 =360
ok done. Thank to me :>
Let x = number of problems on test
If he got 14 wrong, then x - 14 is the number correct.

x - 14 = .72x
.28x - 14 = 0
.28x = 14
x = 50
The test consisted of 50 problems.
8x = -104 (I like to flip mine around like this, but it doesn't matter).
Now, you subtract 8 from both sides because you are doing the inverse.
-104 - 8 = -112
x=-112
Hope this helps!
Have a nice day!
$299 and $199 adds up to 498, including the tax rate 7.5% and your total is $535.35