Arrange these lunch buyers from greatest to least assuming they buy lunch 5 days per week: alice spends $3 per day, betty spends $25 every 2 weeks, and cindy spends $75 per month.

Alice spends $3 per day, so for in a week and upto 5 weeks, Alice spend =$3*5*5 = $75

Betty spends $ 25 every 2 weeks, so for 5 weeks , she spends= 25+25+12.5

= $62.5

Cindy spends $ 75 per month, and on an average there are less then 5 weeks in a month . SO for 5 week, it must be greater than $75 .

So the order is

Cindy>Alice>Betty

a=24; b=12

step-by-step explanation:

a/b=2: 1

a=2b

36/(1+2)=12

b=12

a=24