吾該啊!!!好緊急的!!!第1題係 ：代表那人講的野......幫我翻譯+解釋(all 問題)要方程式

1. Miss Fan: 你們的年齡是多少?
妹妹: 我的姐姐比我大4年
姐姐: 西施死時44歲. 這正是我們兩人14年後的歲數總和.
請替miss fan找出她們的歲數.

small sister's age: X
elder sister's age: Y

X = Y - 4

X + 14 + Y + 14 = 44
X + Y = 16
X = 16 - Y

16 - Y = Y - 4
2Y = 20
Y = 10

X = 10 - 4
X = 6

Therefore, small sister and elder sister's ages are 6 and 10 respectively.

2. alex, ben 和 curtis 分別提拿77kg 的貨物
alex拿的是ben拿的三分之一, 而ben拿的是curtis的一倍.
請問ben拿了多是kg的貨物?

Alex = A, Ben = B, Curtis = C
A = 1/3 B

B = 2C

therefore, A = 2/3 C

2/3 C + 2C + C = 77
11/3 C = 77
C = 21

therefore, Alex = 14kg, Ben = 42kg, Curtis = 21kg

3. alan跟anita替一間店舖銷售了129的紀錄而總銷售額為$12,615.
alan跟anite的銷售價分別為$110跟$95
a. alan替店舖的銷售量是多少?
b. anita的銷售量是多少?

Alan = X
Anita = Y

X + Y = 129
X = 129 - Y

110X + 95Y = 12615
110(129 - Y) + 95Y = 12615
14190 - 110Y + 95Y = 12615
15Y = 1575
Y = 105

X = 129 - 105
X = 24

therefore, Alan sold 24 records while Anita sold 105 records.