A number is 1/7 another number. the difference of the number is 18. assume that you are subtracting the smaller number from the larger number. find the number
a = the smaller number
b = the larger number
a = 1/7 b
b - a = 18
b - 1/7b = 18
6/7b = 18
b = 21
a = 1/7 * 21
a = 3
Answer:
21 and 3
Step-by-step explanation:
Let's call the small number \(x\) and the larger number \(y\).
According to the problem:
\(x=\frac{1}{7}y\)
And when you substract the smaller number from the larger number you get 18:
\(y-x=18\)
substituting the first equation in the second one:
\(y-\frac{1}{7}y=18\frac{6}{7}y=18\\ y=\frac{18*7}{6} =3*7=21\\y=21\)
the larger number is 21.
Using the first equation to find \(x\):
\(x=\frac{1}{7}y\\ x=\frac{1}{7} (21)\\x=3\)
the smaller number is 3.