Consider 3 girls are doing an embroidery work. Let g be the number of hours needed for the first girl to complete the work and h be the number of hours needed for the second girl to complete the work.
If the number of hours needed for the third girl is the sum of the hours needed to complete the work by the first girl and 3 hours less than the hours needed to complete the work by the second girl, write the expression for the total hours needed for the third girl to complete the work.
No. of hours needed for first girl = g
No. of hours needed for second girl = h
So, number of hours needed for third girl = g + (h - 3).