Answer:
<u>The exponential model is: Cost after n years = 400 * (1 + 0.02)ⁿ</u>
Step-by-step explanation:
1. Let's review the information given to us to answer the question correctly:
Cost of the TV set in 1999 = US$ 400
Annual increase rate = 2% = 0.02
2. Write an exponential model to represent this data.
Cost after n years = Cost in 1999 * (1 + r)ⁿ
where r = 0.02 and n = the number of years since 1999
Replacing with the real values for 2020, we have:
Cost after 21 years = 400 * (1 + 0.02)²¹
Cost after 21 years = 400 * 1.5157
Cost after 21 years = $ 606.28
The TV set costs $ 606.28 in 2020.
<u>The exponential model is: Cost after n years = 400 * (1 + 0.02)ⁿ</u>
Try 12x3.14 for your answer hope it’s work
Answer:
4
Step-by-step explanation:
This situation has two unknowns - the total number of half dollars and the total number of quarters. Because we have two unknowns, we will write a system of equations with two equations using the two unknowns.
- h+q=31 is an equation representing the total number of coins
- 0.50h+0.25q=11 is an equation representing the total value in money based on the number of coin. 0.50 and 0.25 come from the value of a half dollar and quarter individually.
We write the first equation in terms of q by subtracting it across the equal sign to get h=31-q. We now substitute this for h in the second equation.
0.50(31-q)+0.25q=11
15.5-0.50q+0.25q=11
15.5-0.25q=11
After simplifying, we subtract 15.5 across and divide by the coefficient of q.
-0.25q=-4.5
q=4
We now know of the 31 coins that 4 are quarters.
Given that D is the mid point of CE ,
So D will bisect CE, it means the length of DE and CD is equal.
=> DE + CD = CE
As DE and CD are equal,
=> DE + DE = CE
=> 2 DE = CE
Putting values from the question,
=> 2( 7x - 1 ) = 10x + 18
=> 14x - 2 = 10x + 18
=> 14x - 10x = 18 + 2
=> 4x = 20
=> x = 20 / 4
=> x = 10 / 2
=> x = 5
Therefore, the value of x is 5
Answer: Paul will be 30 years old
Step-by-step explanation:Let the age of her sister be x, then from the given data
=> 4x = 20
=> x = 5 years
The age of her sister is 5 years
In the second case, paul is twice as old as his sister
=> Age of paul = 2(x)
=> Age of paul = 10 years
Paul will be 10 years old when he is twice as old as his sister
