In calculating this, you would have to find the unit price first.
$13 per 3 1/4 yards is also equal to $4 per yard.
Then you would have to find out the other ones' unit prices.
a) $16 per 4 2/3 yards is equal to around $2.82 per yard, so No
b) $11 per 2 3/4 yards is equal to $4 per yard, so Yes
c) $26 per 6 1/2 yards is equal to $4 per yard, so Yes
I solved these by dividing the amount of money by the amount of string.
