johnsonjermille9
johnsonjermille9 johnsonjermille9
  • 20-01-2021
  • Mathematics
contestada

The average age of three people running for election is 42. A fourth person joins the race and the average drops to 40. What is the fourth person's age?​

Respuesta :

BigBrainBigMuscle
BigBrainBigMuscle BigBrainBigMuscle
  • 20-01-2021

Call the four people [tex]abc[/tex] and [tex]d[/tex].

We know:

[tex]\frac{a+b+c}{3}[/tex][tex]=42[/tex]

and

[tex]\frac{a+b+c+d}{4}[/tex][tex]=40[/tex]

Thus:

[tex]a + b + c = 126[/tex]

[tex]\frac{126+4}{4} = 40[/tex]

[tex]126 + d =160[/tex]

[tex]d = 34[/tex]

Answer Link

Otras preguntas

Decide whether to use saber or conocer to talk about the following people, places, and activities. 1. hablar español saber conocer 2. la profesora saber conocer
what is 1 1/2 - 3/32 i need help asap
Why would the country benefit from a Strong national government
the president should have the power to use tax money in order to develope new technologies. who said it Hamilton or jefferson ​
Why did the British government issue the Proclamation of 1763? Britain wanted to avoid further wars with Native Americans. Britain was involved in another expen
I'm giving 15 points to whoever an help me!!
Fred took a math quiz last week. There were 100 problems on the quiz and Fred answered 30% of them correctly. How many problems did Fred get correct?
the answer to 1+1 is 2
a+b+c d+e+f please guys i need help
what is the exit stage of a business in finance?