✔ 最佳答案
1) 7分之3 除 1又2分之1 乘 8分之5
= (3/7)/(1+1/2) * (5/8)
= (3/7)/(3/2) * (5/8)
= (2/7) * (5/8)
= 5/28
2) 4又9分之2 乘 3又3分之2 除 1又18分之1
= (4+2/9) * (3+2/3)/(1+1/18)
= (38/9)(11/3)/(19/18)
= 44/3
3)
5分之4 乘 6又7分之3 除 2又2分之1
= (4/5)(6+3/7)/(2+1/2)
= (4/5)(45/7)/(5/2)
= 72/35
4) 9分之5 除 7分之4 乘 15分之2
= (5/9)/(4/7) * (2/15)
= 7/54
5)
9又8分之1 乘 4又11分之4 除 1又22分之5
= (9+1/8)(4+4/11)/(1+5/22)
= (17/8)(48/11)/(27/22)
= 68/9
6) 2又3分之2 除 7分之2 乘 4分之3
= (2+2/3)/(2/7) * (3/4)
= (8/3)/(2/7) * (3/4)
= 7
7)
10又6分之5 除 4又8分之7 乘 16分之9
= (10+5/6)/(4+7/8) * (9/16)
= (65/6)/(35/8) * (9/16)
= 39/28
8) 3又5分之3 乘 2又1分之4 除 9
= (3+3/5)(2+4)/9
= (18/5)(6)/9
= 12/5
44/3 > 68/9 > 7 > 12/5 > 72/35 > 39/28 > 5/28 > 7/54
9) mum have 花布 16又4分之1 use 一半 to make 5 個枕頭套,每個枕頭套要用布多少米?
每個枕頭套要用布
= (16+1/4)(1/2)/5
= (65/4)(1/2)/5
= 13/8 米
10)
cola 每瓶 have 1又10分之3升,把2又2分之1瓶 cola 分成每 8分之1升 1cup,可分成多少杯?
可分成
= (1+3/10)(2+1/2)/(1/8)
= (13/10)(5/2)/(1/8)
= 26杯
11)
一個重 1又2分之1公斤的木瓜售 12又5分之3元。爸爸買了一個 3又3分之4 公斤重的木瓜,應付多少元?
應付
= (12+3/5)/(1+1/2) * (3+3/4)
= (63/5)/(3/2) * (15/4)
= 42/5 * 15/4
= 63/2元
12) i run
1又8分之7 km,use 9又12分之11。if i 以相同速度跑 2 又7分之4 km,共要多少 mins ?
共要
= (9+11/12)/(1+7/8) * (2+4/7)
= (119/12)/(15/8) * (18/7)
= 68/5 mins