Answer:
First mechanic worked 20 hours and second mechanic worked 5 hours
Step-by-step explanation:
Let the number of hours the first mechanic worked = 
Let the number of hours the second mechanic worked = 
Therefore, we can write 2 equations and then solve them simultaneously:
Rearranging the first equation: 
and substituting into the second equation to find :
Now sub 
into the first equation to find
Therefore, first mechanic (a) worked 20 hours and second mechanic (b) worked 5 hours
Answer: The original number is 15.
Step-by-step explanation:
The type of graph I would use for a set of categorical data with 25 people surveyed is bar graph.
<h3>Which types of graphs are good for categorical data?</h3>
The type of graph or chart that is good for showing categorical data are:
- Frequency tables
- Pie charts
- Bar charts
Note that bar graph is one of the the most appropriate graphical form of displays for any categorical variables.
Learn more about bar graph from
brainly.com/question/24741444
The equation of the circle is (x - 4)² + (y - 6)² = 16. The correct option is the second option (x - 4)² + (y - 6)² = 16
<h3>Equation of a circle </h3>
From the question, we are to determine the equation of the circle
The equation of circle is given by
(x - h)² + (y - k)² = r²
Where (h, k) is the center
and r is the radius
From the given information,
The two circles are concentric
∴ (h , k) = (4, 6)
But the other circle has a radius that is twice as large
∴ r = 2 × 2
r = 4
Thus,
The equation of the circle becomes
(x - 4)² + (y - 6)² = 4²
(x - 4)² + (y - 6)² = 16
Hence, the equation which represents a circle that is concentric with the circle shown but has a radius that is twice as large is (x - 4)² + (y - 6)² = 16. The correct option is the second option (x - 4)² + (y - 6)² = 16
Learn more on Equation of a circle here: brainly.com/question/1506955
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