中2數學解題

(1.)
5 : 12 = 10 : x
5x = 12 * 10
5x = 120
x = 24


(2.)
Something is missing.

If it is:
x kg : 1 kg = $24 : $32
x : 1 = 24 : 32
32x = 1 * 24
32x = 24
x = 3/4


(3.)
15 L : x L = 70m : 28m
15 : x = 70 : 28
70x = 15*28
70x = 420
x = 6


(4.)
y kg : 10 kg = 2 L : 8 mL
y kg : 10 kg = 2000 mL : 8 mL
y : 10 = 2000 : 8
8y = 10 * 2000
8y = 20000
y = 2500

2010-03-26 00:51:52 補充：
(2.)
x kg : 4 kg = $24 : $32
x : 4 = 24 : 32
32x = 4 * 24
32x = 96
x = 3

2010-03-26 00:53:02 補充：
(5.)
1 : 2/3 = x : 4
(2/3)x = 1 * 4
2x/3 = 4
2x = 3 * 4
2x = 12
x = 6

(1.) 5:12=10:x
x=24

(2) xkg:4kg=$24:$32
x=3

(3.) 15L:xL=70m:28m
x=6

(4.)ykg:10kg=2L:8mL
y=2500

(5.) 1:2/3=x:4
x=6

1) 5 : 12 = 10 : x
5x = 12 乘10 (交叉相乘)
5x = 120
x = 24

2) x kg : 4 kg = $24 : $32
x : 4 = 24 : 32
32x = 4乘24 (交叉相乘)
32x = 96
x = 3



3) 15 L : x L = 70m : 28m
15 : x = 70 : 28
70x = 15乘28 (交叉相乘)
70x = 420
x = 6


4) y kg : 10 kg = 2 L : 8 mL
y kg : 10 kg = 2000 mL : 8 mL
y : 10 = 2000 : 8
8y = 10乘2000 (交叉相乘)
8y = 20000
y = 2500

5) 1 : 2/3 = x : 4
(2/3)x = 1乘4 (交叉相乘)
2x/3 = 4
2x = 3乘4
2x = 12
x = 6

(1.) 5:12=10:x
5/12=10/x
x=24

(2) xkg:kg=$24:$32
如果你個題目係:xkg:1kg=$24:$32
x/1=24/32
x=0.75

(3.) 15L:xL=70m:28m
15/x=70/28
x=6

(4.)ykg:10kg=2L:8mL
y/10=2/8
y=2.5

1.5:12=10:X
10: 24=10:X
X=24
2.X kg:kg=$24:$32
X/1 = 24/32
X=0.75
3.15L:X L=70m:28m
15/x=70/28
x=6

1) 24kg

2) did you forget to type some numbers in?

3) 6xL

4)2.5 kg

i think correct lah...==""