Answer:
21,550
Step-by-step explanation:
An increase of 5% means the population is multiplied by 100% +5% = 1.05. This occurs each year for 12 years, so the multiplier is ...
1.05¹² ≈ 1.7958563
When the initial population is multiplied by this factor, it becomes ...
12,000×1.7958563 ≈ 21,550
Maria = x
Tom = y
Use substitution
x+y=30
2y=x
2y+y=30
3y=30
y=10
Tom is 10 years old.
x+y=30
x+10=30
x=20
Maria is 20 years old.
Answer:
Function: 
Amount earned for 10 hours of work: 
Step-by-step explanation:
Let be "x" the number of hours worked on a project and "y" the total amount Luigi charges for a project.
Based on the data given in the exercise, you can identify that:
- $140 is a fixed amount.
- For each hour worked on the project, Luigi charges $25. This can be expressed as:

Then, the total amount he charges for a project is the sum of $140 and
. This can be represented with the following function:

To calculate the amount of money earned for 10 hours of work, you must substitute
into the function and evaluate. Then:

34% = 0.34
120 * 0.34 = 40.8
Solution: it is 40.8