唉.....做做下又唔識啦......聽日要交呀~幫下手呀~= =

.新春將至~某公司給45名員工送上每人價值$200/$300的現金禮券...如果這些禮券總值$11800~有多少名員工收到$200禮券??????


200 X + 300 Y = 11800
X + Y = 45

200X = 11800 – 300Y
X = 45 – Y

200 (45 – Y) = 11800 – 300Y
45 – Y = 59 – 1.5 Y
0.5Y = 14
Y = 28
X = 45 -28
X = 17
有17名員工收到$200禮券



2.姊妹兩人分一筆$2120的款項~姊妹用去所得款項的5分之1~而妹妹則用去所得款項的6分之1~如果姊姊(俾)妹妹凰多用去$13~每人分得多少錢???


X + Y = 2120
1/5 X – 1/6 Y = 13

X = 2120 – Y
X= 5(13 + 1/6 Y)

X = 2120 – Y
X = 65 + 5/6 Y

2120 – Y = 65 + 5/6 Y
2120 – 65 = 5/6 Y + Y
2055 = 11/6 Y
Y = 1120.91 (妹)
X = 2120 – 1120.91 = 999.09 (姊)


3.上週~子勤溫書的時間是永明的3倍~本週~兩人溫書的時間都增加6小時~結果子勤溫書的時間(俾)永明多12小時~
3a .在上週~子勤溫書的時間是多少???
3b.在上週~永明溫書的時間是多少???


X = 3Y
(X + 6) – (Y +6) = 12

X = 3Y
X + 6 – Y – 6 = 12

X= 3Y
X = 12 + Y

3 Y = 12 + Y
2Y = 12
Y = 6 (在上週~永明溫書的時間是 6小時)
X= 18 (在上週~子勤溫書的時間是18小時)

1. a + b = 45
a = 45-b
200a + 300b = 11800
200 (45-b) + 300b = 11800
9000-200b + 300b = 11800
100b = 11800-9000
100b = 2800
b = 28
a = 45-28
a = 17
17 名員工收到$200禮券


2. a + b = 2120
a = 2120-b
1/5a - 1/6b = 13
1/5 (2120-b) - 1/6b = 13
424-1/5b-1/6b = 13
424 - 11/30b = 13
424 - 13 = 11/30b
411 = 11/30b
411/11 x 30 = b
b = 1121
a = 999
姊姊 = 999 妹妹 = 1121


3.子勤溫書的時間 = a
永明溫書的時間 = b
a = 3b
(a+6)-(b+6) = 12
3b+6-b-6 = 12
2b = 12
b = 6
a = 6 x 3
a = 18

1. 11800除200=59(名)
2.2120除2, 1060-13=1047(錢)
第3題真係唔識....
sor