the mean of four consecutive even numbers is 15.the greatest of these numbers is a1.the least of these numbers is a2.
\(\dfrac{x+(x+1)+(x+2)+(x+3)}4=\dfrac{4x+6}4=15\implies 4x+6=60\implies 4x=54\implies x=9\)
which means \(a_1=x=9\) and \(a_2=x+3=12\)
Answer: The greatest no a1 is 18 and smallest no a2 is 12
Step-by-step explanation:
Let the consecutive even numbers be
x, x+2 , x+4 , x+6
Given mean of four nos =15
Now mean = Sum of all observations/No of observations
15 = \(\frac{x+x+2 + x+4 +x + 6}{4}\)
4x +12 =15×4
4x + 12 = 60
Subtracting 12 both sides
4x + 12- 12 =60 - 12
4x = 48
Dividing both sides by 4
x=12
Hence the smallest no i.e. a2 is 12
Other nos be 12 +2 =14, 12+4 =16, 12 +6= 18
The greatest no i.e. a1 = 18
Hence the nos are 12, 14, 16, 18