I can't understand sum of numbers.

Question

The sum of three numbers is 131. The third number is 4 times the first. The first number is 5 less than the second what are the numbers?

Answer 1

first number = x

second number = x+5

third number = 4x

total = 6x+5 = 131

x=21

second number 26

third number = 84.

Answer 2

Hi Lexi

 

Let us assume the three number are: a, b and c so that:  

 

                                                                   a + b + c = 131

 

From the problem we know that: c = 4a ,  and  a = b -5 (or  b = a +5).

 

 

                                                              a + a +5 + 4a = 131

                                                              

                                                              6a + 5 = 131

       

                                                              6a = 126

 

                                                                a = 21, then b = a +5 = 26, and c = 4a = 84.

 

The three numbers are 21, 26 and 84.