30% decrease
175 divided by 250 = 0.7
1 - 0.7 = 0.3
0.3 = 30%
Answer: The copy machine makes 171 copies in 4 minutes and 45 seconds.
Step-by-step explanation:
Let's dissect the question. The copy machine makes 36 copies per minute.
36 per min.
To see how many copies it makes in 4 minutes and 45 seconds, we multiply 36 * 4.75. 45 seconds is 3/4ths of a minute, or 0.75 of a minute.

It makes 171 copies in 4 minutes and 45 seconds.
So first of all you count all the blocks, so it will be 16 blocks (4x4) sideways and horizontal.
A = 16/4 marked blocks = 25%
B = 16/8 marked blocks = 50%
C = 16/6 marked blocks = ?
D = 16/10 marked blocks = 62,5%
<em>So answer would be A </em>