David and Karen have a goal to read 5000 pages together by the end of the summer

Question

*David reads 60 pages everyday

*Karen reads 25% more than David

They created a model they believe works.

135d=5000

They invite their friend Kim to read with them. Kim reads 40% fewer pages than Karen.

What is their new equation?

Answer 1

135d = 5000 assumes that David will read 60 pages a day and Karen will read 75, since 25% more than 60 is 75.

We now have to look at Kim's contribution. She will read 40% fewer pages than Karen.

This means she only reads 60% of Karen's 75 pages. 60% of 75 gives us 45 pages.

Adding Kim's contribution of 45 pages a day to their combined total of 135 pages a day, their new model is

180d=5000

Answer 2

David reads 60 pages per day.

Karen reads 25% more than David, so she reads 60*1.25 = 75 pages per day.

Kim reads 40% less than Karen, so she reads 75*0.6 = 45 pages per day.

Together they read 60 + 75 + 45 = 180 pages per day.

So their new equation is 180d=5000