Question

find a number whose 1/3 part exceeds its 1/5 part by 20

Answer 1

let the number be x
1/3 of x means 1/3x
1/5 of x mean 1/5x

one by third part exceeds the one by fifth part,so

1/3x=1/5x+20
1/3x= x+100/5
5( 1/3x) = x+100 [ by transposing 5 to left side of equation]
5/3x= x+100
5x = (x+100)3 [ by transposing 3]
5x = 3x+300
5x-3x= 300 [ by transposing 3x]
2x= 300
x= 300/2 [ by transposing 2]
x = 150