Answer:
The parts of the number are 200 and 320
Explanation:
System of Equations
Suppose a and b are the two parts. They must meet two conditions:
![a+b=520\qquad\qquad [1]](https://img.qammunity.org/2021/formulas/mathematics/high-school/1p12kcpcyamswrg0s7zckny37a5t22thu9.png)
![\displaystyle (a)/(b)=(5)/(8)\qquad\qquad [2]](https://img.qammunity.org/2021/formulas/mathematics/high-school/b1b0hfxuizpwtbp1ntdv5zhfv4tdgd5ef3.png)
From [1], we have:

Replacing in [2]:

Cross-multiplying:

Operating:

Joining like terms:

Solving:

a=200
Since:

b=320
The parts of the number are 200 and 320