我有幾題數唔識(小六),(要列式),幫幫忙!!

1. 60/100 + (37.5/100 X 2/3 ÷ 62.5/100)
=60/100 + (75/200 X 2/3 X 200/125) 左手面60同100約左之後變3/5, 右手面200同200相約,75同125約左之後,75變3,125變5,3再同3約
=3/5 + 2/5
=5/5 = 1

2 今年比去年輕:
=(60-54)/60
=6/60
=1/10 = 10%

3 四年級學生人數:
=80 x120/100 x 125/100
=80 x 6/5 x 5/4 5同5約左, 6同4約左之後變3/2
=80 x3/2 =120人

2007-03-12 22:10:54 補充：
第1條: 記住先乘除後加減,同埋d百分數,例如37.5%,要變番做整數既分數,即係75/200,咁就會約下約下約走哂d野好易計架喇第2條: 記住用60做分母,通常錯都係用左54做分母第3條: 如果用計數機就好易,不過記住要好似我咁變番哂佢地做分數先至會滿分(尤其是考試果時)

1) 60%+37.5%x3分之2÷0.625 = ?
= 60/100+375/1000 x 2/3 / 625/1000
= 3/5 + 375/1000 x 2/3 x 1000/625
= 3/5 + 375/1 x 2/3 x 1/625
= 3/5 + 3/1 x 2/3 x 1/5
= 3/5 + 1/1 x 2/1 x 1/5
= 3/5 + 2/5
= 1

2) 張先生去年重60公斤,今年只得54公斤,今年比去年輕百分之幾?
(60-54)/60 x 100%
= 10%


3) 六年級有學生80人,五年級比六年級多20%,四年級比五年級多25%,問四年級有學生多少人?
80 x (1+20%) x (1+25%)
= 80 x 1.2 x 1.25
= 120

1. 97.5%x3分之2 ÷0.625
=65%÷0.625
=104

2. 60-54/60*100%
=10%

3. 80*(1+20%)*(1+25%)
=120

1)60%+37.5%x3分之2÷0.625
=0.6+0.375x1.5÷0.625
=0.6+0.9
=1.8

2)(60-54)/60x100%
=10%

3)五年級有：80(1+20%)=96
四年級有：96(1+25%)=120人

好耐無計了～～如果錯左～就抱歉了～
睇下仲有冇人答．．．．