Question

A man has only 20 paisa coins and 25 paisa coins in his purse , if he has 50 coins in all totalling Rs 11.25, how many coins of each kind does he have

Answer 1

Suppose he has ,
x no. of 20 paisa coins
and y no. of 25 paisa coins
A/Q. x+y = 50. ........(1)

y = 50 - x.

and. 20x + 25y = 1125. ....(2).


Putting value of y from 1 in 2

20x + 25 (50 - x) = 1125

20x - 25x + 1250 = 1125

1250-1125 = 5x
125 = 5x
x = 25. and y = 25.

Hope this helps and my answer is correct.

Answer 2

$\bold \color{green} { \underline { \underline \red{ \green\star \: required \: answer}}} \star$

Let the number of 20 paisa coins be x and that of 25 paisa coins be y. then,

$\bold{x + y = 50}$

total value of 20 paisa coins = 20x paisa

total value of 25 paisa coins = 25y paisa

$\bold{so \: that \: \: 20x + 25y = 1125 }\\ \bold{ \implies4x + 5y - 225 = 0}$

now by using corss-multiplication, we have

$\bold{\frac{x}{ - 225 + 150} = \frac{ - y}{ - 225 + 20} = \frac{1}{5 - 4} }$

$\bold{\implies \frac{x}{25} = \frac{y}{25} = \frac{1}{1}}$

$\bold{\implies \: x = 25 \: \: and \: y = 25}$

hence, there are 25 coins of each kind..