Question

Ram has a total of rs12 of denomination 50p,20p,10p. The number of 50p coins is 4 times the number of 20p. The total number of coins is 35. How many coins of denomination does he have ?

Answer 1

Let a ,b ,c be the number of 50p, 20p,10p respectively
a=4b
No of coins= 35
ie, a+b+c=35
4b+b+c=35
5b+c=35
c= 35-5b... equation (1)
Money ram have is 12 rs ie,1200p

ie, a*(50) +b(20) +c(10) =1200
ie, 4b*(50) +b(20)+ c*(10) =1200...eqn(2)
Put eqn (1) in (2)
4b*(50) + b(20) + (35-5b)*10=1200
ie, 200b+ 20b+ 350-50b=1200
170b=1200-350
170b= 850
b=850/170= 5
a= 4b= 4*5=20
From eqn (1) . c=35-5b=35-25=10
ie, ram have 20 number of 50p, 5 number of 20p and 10 number of 10p