Answer:
$15
Step-by-step explanation:
It is given that,
Last weekend, Nina mowed 4 lawns and received $60. This weekend she mowed 6 lawns and received $90.
We need to find the constant of proportionality.
First we can find the money received when she mowed 1 lawn for last weekend.
4 lawns = $60
1 lawn = $15
Then, we will find the money received when she mowed 1 lawn for this weekend.
6 lawns = $90
1 lawn = $15
Hence, the constant of proportionalityis $15.
