During a sale at the bookstore, books sold for $4 and magazines sold for $3.50. Jan spent $29 and bought a total of 8 books and magazines. How many of each did she buy?

2 books and 6 magazines

Step-by-step explanation:

4b+3.5m=29

b+m=8

subtract the m from both sides

b=8-m

plug 8-m in for b in the first equation

4(8-m) +3.5m=29

32-4m+3.5m=29

subtract the 32 and combone like terms

-0.5m=-3

divide by .5

m=6

plug 6 on for m in the second equation

b+6=8

subtract 6

b=2

answer: 180

step-by-step explanation:

12-2=10

20-2=18

18x10=180

it costs $20 to interview each person for a survey. find the cost to obtain a +- 3% margin of error.

step-by-step explanation:

copy and paste, put it in google