Can someone correct them

9)Science:Jose rode his trail bike for 10miles. two-thirds of the distnace was over a mountain trail. How long is the mountain trail?

My answer: 2/3-10=9 miles

10) perform the indicated operations
3 and 3/4 (divided by ) 1 and 3/8

My answer:2.72

9) 2/3 of 10 is not 9. Try again
2/3 of 10 is the same as 2/3 x 10.

10)Close, but not quite right. In decimal form the answer is
2.7272727... , so 2.73 is closer than 2.72 when you round it off.

In fractional form it is
15/4 divided by 11/8
= 15/4 x 8/11 = 30/11
That is the exact answer.