1.十五分之十四×7 2.
=(1-1/15)*72
=72-72/15
=67又1/5
2.二十分之十九乘六×63
=(1-1/20)*63
=63-63/20
=59又17/20
3.127×二十五分之四
(125+2)*4/25
=20+8/25
=20又8/25
4.98×九十九分之五
=（99-1）*5/99
=5-5/99
=4又94/99