Below is an instruction that describes a task. Write a response that appropriately completes the request in Thai. Please answer in Thai.

### Instruction:
Miss Grayson's class raised $50 for their field trip. Aside from that, each of her students contributed $5 each. There are 20 students in her class, and the cost of the trip is $7 for each student. After all the field trip costs were paid, how much is left in Miss Grayson's class fund?

### Response:
 20 x $5 = $<<20*5=100>>100 ถูกรวบรวมจากนักเรียน
คลาสของครูเกรย์สันมีเงินรวม $100 + $50 = $<<100+50=150>>150
7 x 20 = $<<7*20=140>>140 เป็นค่าใช้จ่ายสำหรับทริปทั้งหมด
ดังนั้น, $150 - $140 = $<<150-140=10>>10 เหลืออยู่