Mr. abernathy purchased a selection of wrenches for his shop. the total cost was $78. he bought the same number of $1.50 and $2.50 wrenches, and half that many $4 wrenches. the number of $3 wrenches was one more than the number of $4 wrenches. how many of each did he purchase? _ $1.50 wrenches _$2.50 wrenches _$4 wrenches _$3 wrenches.