posted by JOY .
You and your friend are both knitting scarves for charity. You knit 8 rows each minute and already have knitted 10 rows.Your friend knits 5 rows each minute and has already knitted 19 rows. When will you both have knitted the same number of rows?
How do I set up this word problem??
first represent the unknown using variable:
let x = time required so that they will have the same number of rows.
recall that rate = quantity/time, or quantity = rate*time
in this problem, quantity refers to number of rows knitted.
to set-up the equation, what we only know is that at this particular time, x, their quantities must be equal. thus we add for both number of rows they initially knitted and their rate times the required time, or:
quantity (of you) = quantity (of friend)
10 + 8x = 19 + 5x
hope this helps~ :)