math(方程式)希望你地幫到me計呢幾條math題)

🎓 學業台小學及中學教育

匿名小客

2006-10-15 12:56 am

Solve the following equations.

1.The difference between two numbers is 10.If the sum of the smaller number multiplied
by 4 and the larger number multiplied by 1/3 is 25,find the two numbers.
2.Teavher gives x pieces of stickers evenly to 8 children.Every child receives 5 stickers,
and 3 stickers are left.Find the total number of stickers.
3.Sophia is 28 years younger than Dick.Gary is 1/4 the age of Sophia.Maria is 18 years
older than Gary.If Maria is 28,how old is Dicky?

更新1:

4.The figure shows a wall formed by 3 kinds of bricks with different lengths. 4.a.If the brick in the middle is (ax+2)cm long,find the lengths of the other two kinds of bricks.Express your answers in terms of x. 4.b.If the length of the wall is 60 cm,find the value of x.

回答 (2)

[匿名]

2006-10-15 1:13 am

✔ 最佳答案

Hey kid I'll help you get started on the first 2. Try the rest yourself~

1) Let the bigger number be X and the smaller number be Y
The difference between two numbers is 10 --> X-Y=10
hence, X=10+Y
If the sum of the smaller number multiplied by 4 and the larger number multiplied by 1/3 is 25 --> 4Y + X/3 = 25
4Y + (10+Y)/3 = 25 (substitue in X=10+Y so you get only one unknown)
12Y + (10+Y) = 75 (multiply 3 on both side to get rid of the denominator ''3")
13Y = 75-10
Y= 65/13 = 5
x= 10+y = 10+5= 15

2) Let the total # of stickers be X
X = 8stickers/child x 5children + 3stickers left
u calculate the final answer yourself

Hope that helps~

參考: my own knowledge

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[匿名]

2006-10-15 1:37 am

1. Let the smaller number be x, larger number be y
y-x=10→(1)
x/4+y/(1/3)=25→(2)
From (2), x=100-12y→(3)
Put (3) in(1), y-(100-12y)=10
y-100+12y=10
13y=110
y=110/13
Put y=110/13 in (2)
x/4+(110/13)/(1/3)=25
x=-20/13
∴the smaller number is -20/3, larger number is 110/13

2. The total number of stickers=8*5+3
=43

3. Gary=28-18=10
Sophia=10*4=40
Dicky=40+28=68

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收錄日期: 2021-04-26 11:58:32
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