F.1數學........增加百分數

條式應該係咁:

新嗰個數 - 舊嗰個數
-------------------- --------- x 100%
.........舊嗰個數

(正數即係增加, 負數即係下降)

1) 他體重增加的百分數是:

(37/56) x100%
= 0.6607(大約) x 100%
= 66.07%

2) 學生人數增加的百分數是:

[(1404 -1300)/1300) x 100%
0.08 x 100%
= 8%

3)飯廳的面積佔全個單位面積的:

(22/55) x 100%
= 0.4 X 100%
= 40%

4) 中一級的學生坐校巴上學的百分數是:

(108/180) x 100%
=0.6 x 100%
= 60%

5) 他採摘的西瓜, 好的有:

1600 x (100% - 7.5%)
= 1600 x 92.5%
= 1600 x 0.925
= 1480個

----------------------------------------------------------------------------------------------

1.
830/N = 20%
830 = N x 20% = N x 0.2
N = 830/0.2
N = 4150

2.
192/P = 75%
192 = P x 75% = P x 0.75
P = 192/0.75
P = 256

3.
132/T = 88%
132 = T x 88% = T x 0.88
T = 132/0.88
T = 150

4.
562.5/K = 150%
562.5 = K x 150% = K x 1.5
K = 562.5/1.5
K = 375


希望幫到你~!!

2006-12-07 12:24:04 補充：
by the way, 呢條你之前唔係問過gar咩?

增加的百分數
=37/56*100%
=3700%/56
=25%

增加的百分數
=1404-1300/1300*100%
=104/1300*100%
=8%

佔全個單位面積的
=22/55*100%
=40%

有
=108/180*100%
=60%

有
=1600*(1-7 1/2%)
=1600*(1-7.5%)
=1600*(1-0.075)
=1600*0.925
=1480

1. 20%N km=830 km
N km=830km/20%
Nkm=166

2.75%$P=$192
$P=256

3.88%T g=132g
Tg=150g

4.150%K mL=562.5
KmL=375

1 ) 56kg - 37kg / 37kg x100%
=51.35%
2) 1404人-1300人 / 1300人 x 100%
=0.08%
3) 22㎡/55㎡ x100%
=40%
4) 108人/180人x100%
=60%
5) 1600個x(1-7 1/2%)
=1480個

2006-12-07 17:46:24 補充：
1) N*20%=830 N=830*5 N=41502) P*75%=190 P=190*4/3 P=760/33) T*88%=132 T=132*25/22 T=1504) K*150%=562.5 K=562.5*2/3 K=375

2006-12-07 17:48:50 補充：
2)應該係8%

答安取一個小數位
1 37/56*100%=66.1%
2 (1404-1300)/1300*100%=8%
3 22/55*100%=40%
4 108/180*100%=60%
5 1600*(1-7.5%)=1480

未知數
1 N*(20%)=830
N=4150
2 P*(75%)=192
P=256
3 T*(88%)=132
T=150
4 K*(150%)=562.5
K=375

1. (56 - 37)/37 = 0.5135 = 51.35%
2. (1404 - 1300)/1300 = 0.08 = 8%
3. 22/55 = 0.40 = 40%
4. 108/180 = 0.60 = 60%
5. 1600(1 - 7 1/2%) = 1600(0.925) = 1480

1. 830/0.2 = 4150 km
2. 192/0.75 = $256
3. 132/0.88 = 150 g
4. 562.5/1.5 = 375 ml