楼主是用60分别乘以0.8和1.2得来的48和72 正确答案应该用60分别除以0.8 1.2所以选E 希望对你有帮助
"20 percent greater than the integer x"=1.2x
"a number 20 percent less than the integer x"=0.8x
T is no more than 1.2x, no smaller than 0.8x
0.8x<=t<=1.2x
t=60:
0.8x<=60<=1.2x
50<=x<=75
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