f.1升f.2既maths..............教教我

Q1)let x be the no.
5x-3x=4
2x=4
x=2

Q2)
有d不明
wt is '45 coins' ??

Q3a)
The value of the 5th month
$1000000(100+5-20/100)
=$850000

becoz $850000-$1000000
=-150000
so the man is lose over a five-month period.

The percentage gain or loss

(150000/1000000)100%

=15% <--final ans.


hope u understand!!!

2008-08-21 20:17:10 補充：
Q2)let x be the no. of $2 coins ,let y be the no. of 5 coins.

x+y=20-----(1)
x=20-y

2x+5y=96-----(2)

sub.x=20-y into (2)
2(20-y)+y=20

2008-08-21 20:21:39 補充：
sor.....&#92;
i think i hv sth wrong in the " 補充"

maybe u ask anthor people
sor......

1) Let x be the number
5x-3x=4
2x=4
x=2

2)
你45個幾多$ ge coins aR!

3a)
The value of the 5th month
$1000000x(100 5-(20/100))
=$850000

( 因為)$850000-$1000000
=-150000
(所以)so the man is lose over a five-month period.

The percentage gain or loss: (150000/1000000)100%

=15%