Savings caleb made $105 mowing lawns and walking dogs, charging the rates shown. if he mowed half as many lawns as dogs walked, how many lawns did he mow and how many dogs did he walk? $7.50 for walking dogs and $20 for mowing lawns

Caleb mowed 3 lawns and walked 6 dogs.  

Step-by-step explanation:

The solution to the problem can be found using a system of equations and the substitution method.  Using 'd' for the amount of dogs walked and 'm' for the amount of lawns mowed, we know that the total amount earned was $105: 7.5d + 20m = 105.  We also know that Caleb mowed half as many lawns as dogs walked or 2m = d.  By sustituting the expression '2m' for 'd' in the first equation:  7.5(2m) + 20m = 105, we can then use inverse operations to solve for 'm':  15m + 20m = 105 or 35m = 105 or m = 3.  Since we now know that the number of lawns mowed is 3, we can find the number of dogs walked by: 2(3) = 6.