$4\frac{4}{9}$ hour
Worker A takes 8 hours to do = 1 job
Worker A takes 1 hours to do =$\frac{1}{8}$ job
Worker B takes 10 hours to do = 1 job
Worker B takes 1 hours to do =$\frac{1}{10}$ job
They together do = $\frac{1}{10}$ + $\frac{1}{8}$ = $\frac{9}{40}$
So A and B together do $\frac{9}{40}$ job in = 1 hour
S0 A and B together do 1 job in = $\frac{1x 40}{9}$ = $4\frac{4}{9}$ hour
560
Let, the number of male be x
Then the number of female be 4x
Total number of male and female = x + 4x = 5x
According to the question,
x+140:4x=2:3
=> $\frac{x+140}{4x}=\frac{2}{3}$
=> 3x + 420 = 8x
=> 5x = 420
=> x = 84
Total number of member be = 5x + 140
= 5 x 84 + 140
= 420 + 140 = 560
24 miles
Total distance = 45 miles.
According to the question,
Yasmin walked 3 miles more.
So both have to walk = 45 — 3 = 42 miles.
Both walked = 3 + 4 = 7 miles in one hour.
So, 7 miles take = 1 hour
42 miles take =$\frac{1×42}{7}$ = 6 hour
Babul walked = 6 x 4 = 24 miles, when they met.
she purchased 7 pieces of brand X pens
Let, Brand X pen = p pieces
Brand Y pen = ( 12 — p) pieces
Cost of p pieces = 4 x p = 4p Tk.
Cost of(12 —p) pieces = Tk. (12 —p) x 2.8
According to the question,
4p + (12 —p) 2.8 = 42
4p + 33.6 — 2.8p = 42
4p — 2.8p = 42 — 33.6
1.2p = 8.4
p = 7
So, she purchased 7 pieces of brand X pens.
