Mean = (total of contributors) / (number of contributors)
For the 6 people in the room, you have
40 = (total of contributors) / 6
(total of contributors) = 6*40 = 240
A 60-year-old left the room, decreasing the total of contributors by 60.
(new total of contributors) = (total of contributors) - 60
(new total of contributors) = 240 - 60 = 180
Then the new mean is
(new mean) = (new total of contributors) / (new number of contributors)
(new mean) = 180 / 6 = 36
The mean age of the remaining 5 people is 36.
Answer:
11
Step-by-step explanation:
The mean is calculated as
mean = 
let the third number be x , then
= 15 ( multiply both sides by 3 to clear the fraction )
34 + x = 45 ( subtract 34 from both sides )
x = 11 ← third number
3.4×10⁻¹⁴ × 1.8×10²⁸
= (3.4 x 1.8) x 10⁽⁻¹⁴⁺²⁸⁾
= 6.12 x 10¹⁴
Answer is A.
Hope it helps!
X-y=-1
x+y=5
y=x+1
x+x+1=5
2x+1=5
2x=4
x=2
y=x+1
y=2+1
y=3
