计算题(39*2/7+2/7*4)÷2/7 7/12-(1/4-5/12) 5-3/2*10/21-2/7
问题描述:
计算题(39*2/7+2/7*4)÷2/7 7/12-(1/4-5/12) 5-3/2*10/21-2/7
答
(39*2/7+2/7*4)÷2/7
=(39*2/7+2/7*4)*7/2
=39*2/7*7/2+2/7*4*7/2
=39+4
=43
7/12-(1/4-5/12)
=7/12-1/4+5/12
=(7/12+5/12)-1/4
=1-1/4
3/4
5-3/2*10/21-2/7
=5-5/7-2/7
=5-(5/7+2/7)
=5-1
=4