Given:
John had to pay a combined electric and gas bill $150.
The electric portion of the bill was $90.
To find:
The ratio of money spent on electric to that on gas.
Solution:
Let x be the amount of gas bill.
The electric portion of the bill was $90 and John had to pay a combined electric and gas bill $150. So,
The gas portion of the bill was $60.
The ratio of money spent on electric to that on gas is:
Therefore, the ratio of money spent on electric to that on gas is 3:2.