Number of 50 Tk. note was 80.
Let, Number of 50 Tk. note = x
& Number of 100 Tk. note = 140 – x
According to the question,
50x + 100(140 – x) = 10,000
=> 50x + 14,000 – 100x = 10,000
= – 50x = -4,000
=> x = $\frac{4000}{50}$
x= 80
Deposit amount was 21,000 Tk.
Let, Karim’s total deposit = x TK
His interest gain at 7% interest = x $\times$ 7% x 5 (I = Pnr)
His interest gain at 5% interest = x $\times$ 5% x 5
According to the question, Difference of interest
(x$\times$7%$\times$S)-(x$\times$ 5%$\times$5)= 2,100
=> $\frac{35x}{100}-\frac{25x}{100}$ = 2100
=> $\frac{35x-25x}{100}$ = 2100
=> 10x = 2,100 x100
x = 21,000
They dig the pond in 12 days.
In 30 days A can dig = 1 pond
In 1 day A can dig= $\frac{1}{30}$ part
Again,
In 20 days B can dig = 1 pond
In 1 day B can dig = $\frac{1}{20}$ part
In 1 day, they together can dig = ( $\frac{1}{30}$+$\frac{1}{20}$) part
= $\frac{2+3}{60}$ = $\frac{1}{12}$ part
They dig $\frac{1}{12}$ part of the pond in = 1 day
They dig 1 or complete part of the pond in =$\frac{1\times12}{1}$ = 12 days
The area of the path is 700 square meter.
The area of the garden is = 60 x 20 = 1,200 Sq. meter
Length without road = 60 – 5 x 2 = 50 meter and
Breadth without road = 20 – (2 x 5) = 10 meter
Without road, the area of the garden is = 50 x 10 = 500 Sq. meter
The area of the road is = 1,200 – 500 = 700 Sq. meter
ans: Rahim has 36 Tk.
Let, the amount of Rahim be Tk. x
The amount of Karim be Tk. x
Rumana has = ( x $\times\frac{1}{2}$) = $\frac{x}{2}$
Amena has = $\frac{x}{2}\times \frac{1}{2}$ = $\frac{x}{4}$
According to the question,
x+x+$\frac{x}{2}$+$\frac{x}{4}$+1 = 100
=> 2x+$\frac{x}{2}$+$\frac{x}{4}$ = 100-1
=> $\frac{8x+2x+x}{4}$ = 99
=> 11x = 99$\times$4
=> x = $\frac{99\times 4}{11}$
x = 36
