Could someone please help me with this EASY math question.?

Math was one of the subjects I failed repeatedly in high school, but does this work:

x + y + z = 100 the sum of 3 numbers is 100

y = 4 * z The second number is 4 times the third

x = z-8 the first number is 8 less than the third

so I have z in all the comparisons, so I can replace the variables in the first line with the "z" sentences

z - 8 + 4z + z = 100

z + 4z + z -8 = 100

6z = 108

z = 18

if z = 18 then

x = 18 - 8 = 10

y = 4 * 18 = 72

z = 18

10 + 72 + 18 = 100

x + y + z = 100

y = 4z

x = z - 8

substitute second and third equations into first equation:

(z - 8) + 4z + z = 100

6z - 8 = 100

6z = 108

z = 108/6 = 18

using second equation:

y = 4(18) = 72

using third equation:

x = 18 - 8 = 10

check using first equation:

10 + 72 + 18 = 100 checks

The numbers are 10, 72 and 18.

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