Question 903770
a=b/2
1/b/2+1/b=1/26
2/b+1/b=1/26
3/b=1/26
b=78
a=78/2

a=39 b=78
check
1/a+1/b=1/x
1/39+1/78=1/26
2/78+1/78=1/26
3/78=1/26
x=26 hours working together
a=39 hours working alone
b=78 hours working alone
ok