So we have to put the value of 1:3 in a ratio
1 : 3
= 3:y
Ask yourself what do I have to multiply one by to get three ( the answer is three)
Because one side is multiplied by three, you have to multiply the right hand side by three to get y
3*3 is 9
Therefore, the y for 3 hours is 9
Then, we have to make another ratio
1:3
= 5:x
Ask yourself what do I have to multiply by one to get five (the answer is five)
So you multiply the other side by five as well
3*5=15
Therefore, the y for five hours is 15