Answer:
youngest=115
middle=150
elder=230
Step-by-step explanation:
let the youngest be x
the middle will be x+35
the oldest will be 2x
x+x+35+2x=495
4x+35=495
4x=495-35
4x=460
x=115
since the youngest is x,the money he will receive is $115.
the middle will be x+35 which is equal to 115+35=$150.
lastly the oldest will be 2x which is equal to 2×115=$230.
Using formula a^2- b^2 = (a-b)(a+b)

Answer: The length of the candle was 13.5 inches before it was lit.
Step-by-step explanation:
Let the length of candle in the beginning be c.
Constant rate of change in length of candle= -1.6 inches per hour
Since rate of change is constant so the length of candle can be represented by a linear function [Linear function has constant rate of change.]
Linear function : f(x)= mx+c , where x= independent variable.
m= constant rate of change and c= initial value of function.
Let x = Number of hours after the candle was lit.
Put m= -1.6 , x= 3 and f(x)= 8.7 , we get

Hence, the length of the candle was 13.5 inches before it was lit.
Answer:
$534
Step-by-step explanation:
89*2=178
178+89(4)=534
Answer: 153
Step-by-step explanation:
When we have a group of N elements, the total number of combinations of K elements ( K ≤ N) is:

Where N! = N*(N - 1)*(N - 2)*...*2*1
In this case, we have a group of 18 people (then N = 18) and we want to see how many different combinations of 2 we can make (K = 2).
Using the above equation we get:

There are 153 different ways in which the manager can do this.