(2-3/4×4/5)÷(1/12+4/15)简算!

题目

(2-3/4×4/5)÷(1/12+4/15)简算!
今天就要!

答案

(2-3/4×4/5)÷(1/12+4/15)
＝(2-3/5)÷(5/60+16/60)
＝7/5÷21/60
＝7/5x60/21
=12/3
=4