Answer:
D. 210
Step-by-step explanation:
The easiest way to calculate this is with a simple ratio. 10/3 = x/63 Simply see how many times three goes into 63 and multiply that number by 10. When you solve this you should end up getting 63/3 = 21, 21*10 = 210 pages. I am so sorry if this explanation wasn't helpful, I tried my hardest to have my explanation make sense.