A lady has some 50 paise coins and some 25 paise coins in her purse if in all she 55 coins totalling Rs. 21.25 how many 50 paise coins she was?please explain each & every step
Answers
number of 25 paise coins=y
x+y=55---(1)
50x+25y=2125
divide each term with 25
2x+y=85----(2)
subtract (1) from (2)
x=30
substitute x=30 in (1) u get
y=25
therefore
number of 50paise coins=x=30
number of 25 paise coins=y=25
Assuming that the number of 50 poise coins be x, and the number of 25 poise coins be y.
What is given in the question?
She has 55 coins in total, so x+y=55 - i) We have arrived at the first equation. Once we get the other equation, we can solve it.
The coins values total up to 21.25 rupees. You can see that the total is in rupees, so convert it to poise for convenience i.e.,2125 poise.
So, the total value of 50 poise coin is 50 x the number of 50 poise coins= 50 x
Likewise, for total value of 25 poise coin is 25 x number of 25 poise coins=25 y
So, the total values of both will be the total value of the money she has.
50 x+25 y=2125 or 2 x+y=85, when you reduce it by dividing the whole equation by 25. - ii) We got the 2nd equation.
2 x+y=85 - i)
x+y=55 - ii)
Subtracting ii) from i)
x= 85-55=>x=30 i.e., the total number of 50 poise coins she has is 30.
Substituting in ii)
30+y=55=>y=25 i.e., the total number of 25 poise coins she has is 25.
The trick is to find 2 equations from which you can solve. Getting the equation is tricky, but after getting those, it's easy.
Thank you.