Question

A and B can do a piece of work in 72 days; B and C can do it in 90 days. In what time can A alone do it​

Answer 1

Answer:

let A and B be X

X+X=72

2X=72

X=72

2

X=36

B=36

let C be x

B+C=90

36+X=90

X=90-36

X=54

C=54

let A be X

A+B+C=X

X+36+54=X

2X=54-36

2X=18

X=18

2

X=6

A=6 DAYS

A CAN DO 6 DAYS ALONE