中學數學題

1.
100/9.72m/sec

=100/9.72 x3600

=37037.0370370(無限個370)m/h=37.037037037.../h

=1000000/27m/h=1000/27km/h

2.11,7,3,-1,...

T(n)=15-4n

13項總和=15-4(1)+15-4(2)...

=13*15-4(1+2+3+4+5+6+7+8+9+10+11+12+13)

=195-4*(13+1)/2*(13+1)/1

=195-392

=-197

3.
實用面積的長度=1-17%
實用面積的闊度=1-8%

實用面積=(1-17%)*(1-8%)

=83%*92%

=76.36%

4.
Let x=該車的標價

180500*125%*95%*85%=x

182192.1875=x

2008-11-09 20:11:35 補充：
我都係F.1

2008-11-09 20:23:07 補充：
4.
Let x=該車的標價

180500*125%=x*95%*85%

225625*100/95*100/85=x

279411 13/17=x

1. 100/9.72 sec = 2500/243 m / sec

2500/243 * 3600 = 1000000/27 m / hour

= 1000/27 km / hour

= 37 1/27 km /hour

2008-11-05 22:00:02 補充：
2.

Find the 13th term of the sequence.

11-(4*12)

= 11-48
= -37
Find the sum of the first thirteen terms.
[11+(-37)]*13/2
= -169

2008-11-05 22:01:37 補充：
3.

length : (100 - 17)% = 83%

width : (100 - 8) % = 92%

83% * 92% = 76.36%

2008-11-05 22:09:29 補充：
4. first find out the selling pice of the car :

180500 * (100 + 25)% = $225625

let A be the 標價 of the car

A *85% * 95% = $225625

IT MEANS 225625 / 85% / 95%

ANS = 237500 * 100 / 95 = $(4750000 / 19) = 250000

標價 = $250000

上面的回答真係有問題...
我得小六喳

1.
100/9.72
=10.288065843621399176954732510288(km per hour)

2.
Find the 13th term of the sequence.
11-(4*12)
= 11-48
= -37
Find the sum of the first thirteen terms.
[11+(-37)]*13/2
= -169

3.
1-(17%+8%)
= 75%
Sorry,Iam not very sure about this answer.

4.The marked price of the car
180500/0.95/1.25
= 152000

我都係F.1,但我唔肯定第3題ge答案.
(STC)

4.
現價(八五折)
180500x0.85
=_____

If三個月前訂購可再享有九五折優恵:
把上題的_____ x 0.95
= _answer_


我只懂一題,我只是F.1 . I hope this can help you......