Question

At the market, 5 light bulbs cost $9.85.
How much do 7 light bulbs cost?

Answer 1

LOOL

Answer 2

have you tried the cross method?

Answer 3

....

Answer 4

what grade do you think i'm in?

Answer 5

So 5?=68.95
?=13.79

Answer 6

The "economic" method would be to find the unit price for 1 light bulb, and then multiply it by 7. The quicker mathematical method would be to set up a ratio/proportion and find the missing variable.

The "economic" approach: It costs $9.85 for 5 bulbs. That means that for 1 bulb, it cost 9.85/5 or $1.97. If we multiply that by 7, we get $13.79.

Answer 7

Both ways work X)

Answer 8

@CShrix I gave you a medal!

Answer 9

Thank you! X)

Answer 10

Your welcome

Answer 11

Bye!