The mean can be found by adding the two numbers and dividing by 2
let the second number be y
(x + y)/2 = 1/2x + 1
solve for y
multiply each side by 2
x + y = 2(1/2x + 1)
distribute
x + y = x + 2
subtract x on both sides
y = 2
ANSWER: the second number is 2
8x-13
1. Distribute 6 to both 2x and -3
5+12x-18-4x
2. Combine like terms
8x-13
The formula of combination is

We have

and


Hence, there are 1001 ways of arranging 10 records from 14 records
Answer:
He must earn $2,400 to cover both leisure and $2,160 for school expenses.
Step-by-step explanation:
Let the total amount Ken must earn be k. Then 10% of that would cover leisure activities and the remaining 90% specifically for school expenses.
Then 0.90k = $2,160, and k = $2,400.
He must earn $2,400 to cover both leisure and $2,160 for school expenses.