If Mo pays 1/2 of the rent then he is paying 50%. Charlie is paying another 25%. This leaves the remaining 25% that Andy pays. Since Andy's payment amount is 450 then that means that 450 is equal to 25% of the total rent. Therefore, we simply need to multiply this amount by 4 to get the 100% of the overall rent.
450 * 4 = $1,800
Finally, we can see that the total rent amount is $1,800
<span>X= math problems
y= science problems
x +y =42
x= y+10
Substitute: (y+10) + y =42
Combine y: 2y +10=42
Solve for y: y= 16
There are 16 science questions and 26 math questions</span>
