It takes a printer 21 2 min to print 24 black-and-white pages and 4 color pages. it takes the same printer 31 4 min to print 30 black-and-white pages and 6 color pages. let b represent the time in minutes needed to print a black-and-white page and c represent the time in minutes needed to print a color page.

Multiply the first equation by 1.5, to get:

(1.5)(24b+4c)+ 1.5 (2.5)

36b + 6c+ 3.75

Subtract the secound equation from this:

6b+ 1/2

b= 1/12

Substituting into the first equation:

24b + 4c +2.5

24* (1/12) +4c +2.5

2+4 +2.5

4c+o.5

c+ 1/8

Therefore, it takes 1/12 minute to print a black-and-white page, and 1/8 minute to print a colored page.

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!

hello! just here for points! though i wish i knew!