Carcass wrote:
When positive integer x is divided by positive integer y, the quotient is 17 and the remainder is 3. When x is divided by (y−3), the quotient is 24 and the remainder is 5. What is the value of x?
A. 169
B. 173
C. 180
D. 204
E. 211
There's a nice rule that says, "
If N divided by D equals Q with remainder R, then N = DQ + R"
For example, since 17 divided by 5 equals 3 with remainder 2, then we can write 17 = (5)(3) + 2
Likewise, since 53 divided by 10 equals 5 with remainder 3, then we can write 53 = (10)(5) + 3
When positive integer x is divided by positive integer y, the quotient is 17 and the remainder is 3So, we can write
x = 17y + 3When x is divided by (y-3), the quotient is 24 and the remainder is 5.So, we can write
x = 24(y - 3) + 5What is the value of x?Since we now have two equations that equal to x, we can write:
17y + 3 = 24(y - 3) + 5Expand and simplify the right side:
17y + 3 = 24y - 67Add 67 to both sides of the equation:
17y + 70 = 24ySubtract 17y from both sides of the equation:
70 = 7ySolve:
y = 10Find the corresponding value of x, just plug
y = 10 into one of our two
equations.
We get:
x = 17(10) + 3 = 170 + 3 = 173Answer: B