a) 470 & 275

b) 390 & 255

c) 410 & 235

d) 430 & 215

correct answer is: c) 410 & 235

**Explanation**

Let, one number is ‘x’

Another number is ‘y’

According to the question,

\left(x+y\right)=645

\rightarrow x=645-y ———(1)

And, x=\large\frac{y}{2} ——–(2)

According to the question,

645-y=\frac{y}{2}

\rightarrow2\left(645-y\right)=y

\rightarrow1290-2y=y

\rightarrow-2y-y=-1290

\rightarrow-3y=-1290

\rightarrow y=\large\frac{-1290}{-3}

\rightarrow y=430

Put the value in no (1) equation, we get:

x=645-430

\rightarrow x=215

\therefore One number is 430 and another number is 215 .**Ans:** The numbers are 430 & 215.

**Other versions of this specific question are:****1. Calculate two numbers whose sum is 645, with one number being half of the other.****2. Find the two numbers when their sum is 645 and one number is half of the other.****3. Determine the numbers if their total is 645 and one number is half the value of the other.****4. What are the two numbers if their sum is 645 and one number is half of the other?**