HeLLP!.............?

Question

The sum of 3 numbers is 42. The second number is 5 less than half of the first number. The third number is 7 more than the first number. What are the three numbers?

Answer 1

Let f be the first number s the second and t the third

From the question we can draw relationships among them

f + s + t = 42 'The sum of 3 numbers is 42'

s = f/2 - 5 'The second number is 5 less than half of the first number'

t = f + 7 'The third number is 7 more than the first number.

f is common in all of these so just plug s's and t's equations into the first equation

f + (f/2 - 5) + (f + 7) = 42

multiply by 2 to clear fractions

2f + f - 10 + 2f + 14 = 84

collect like terms

5f + 4 = 84

subtract 4 from both sides

5f = 80

divide both sides by 5

f = 16

plug this into s's and t's equation

s = f/2 - 5

s = (16)/2 - 5
s = 8 - 5
s = 3

t = f + 7

t = (16) + 7
t = 23

your answers are f = 16, s = 3 and t = 23

the check

f + s + t = 42
(16) + (3) + (23) = 42
42 = 42 we're correct

hope this helps!

Answer 2

16
3
23