中一數丫``救我!!`

Peter has $9 more than Paul,and Philips is 1/3 of peters.How much money does each of them have if they have a total of $61?
Let Philips has $x, Peter has $3x and Paul has $(3x-9).
x+3x+(3x-9)=61
7x-9=61
7x=70
x=10
Philips has $10, Peter has 10*3=$30 and Paul has 30-9=$21.

The difference between two numbers is 10.If the sum of the smaller number multipliedby 4 and the larger number multiplied by 1/3 is 25,find the two number.
Let the larger number is x, and the smaller number is (x-10).
4(x-10)+x/3=25
4x-40+x/3=25
4x+x/3=65
(13x)/3=65
13x=195
x=15
The large number is 15, and the smaller number is 5.

2006-10-18 20:06:10 補充：
well done

Peter has$9 more than Paul, and Philip's is 1/3 of Peter.
How much money does each of them have if they have a total of $61

Let x be Peter
Let y be Paul
Let z be Philip

x = y + 9 -------------------------1
z = x/3 ----------------------------2
x + y + z = 61 -----------------3

From (1),
y = x – 9 -----------------------4

Sub (2) and (4) into (3),
x + ( x - 9 ) + x/3 = 61
2x – 9 + x/3 = 61
2x + x/3 = 70
6x + x = 210
7x = 210
x = 30

From x = 30, sub into (4) and (3)
y = 30-9
y = 21

30 + 21 + z = 61
z = 10

Therefore, Peter has $30, Paul has $21 and Philip has $10.

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The difference between two numbers is 10.If the sum of the smaller number multipliedby 4 and the larger number multiplied by 1/3 is 25,find the two number.

Let x be the smaller number
Let y be the larger number

y – x = 10 ---------------------1
4x+y/3 = 25 --------------------2

From (1),
y = x + 10 ----------------------3

sub (3) into (2)
4x + (x + 10)/3 = 25
12x + x + 10 = 75
13x + 10 = 75
13x = 65
x = 5

From x = 5, then sub into (1),
y – 5 = 10
y = 15

Therefore, 5 is the smaller number and 15 is the larger number.

Peter has $9 more than Paul,and Philips is 1/3 of peters.How much money does each of them have if they have a total of $61?
let Philip has x dollars
then
Peter has 3x dollars
Paul has 3x-9 dollars
x+3x+3x-9=61
x=10
Philip has 10 dollars, Peter has 30 dollars,Paul has 21 dollars

(x-4)-(x-1/3)=25

4(x-10)=x/3=25

你打錯了嗎?


2006-10-17 02:08:34 補充：
let the small number is x, then the large number is 10 x4x 1/3(10 x)=2512x 10 x=7513x=65x=5the two number are 5, 15 我今次做佐開荒牛了﹐CHEESE

2006-10-17 02:10:19 補充：
0的空位是加號