We know that
<span>Joey and Rita paint a room in 8 hours
so
100%----------> 8 hours
X%----------> 1 hour
x=100/8-----> 12.5%
that means
</span>Joey and Rita paint 12.5% of a room in 1 hour
Billy paint a room in 12 hours
so
100%----------> 12 hours
X %------------> 1 hour
x=100/12----> x=8.33 %
that means
Billy paint 8.33% of a room in 1 hour
i<span>f all three work together
then
All three paint (12.5%+8.33%) in 1 hour
20.83%------------> 1 hour
100%------------> x
x=100/20.83-----> x=4.8 hours
the answer is
4.8 hours</span>
Consider the attached figure. All the triangles shown are similar, so
CB/CA = CD/CB
30/50 = projection/30
projection = 30^2/50
projection = 18
Answer:
Washing cars= 4 hours
Walking dogs= 10 hours
Step-by-step explanation:
You want to start by creating equations. So one thing we know is that he makes $9 an hour washing cars(x) and $8 walking dogs(y).
$9x+$8y=$116
The second Equation is based off of the hours worked. We know that he worked 6 hours more walking the dogs than he did washing cars, so we can take x(being the washing hours) and add 6 to it to equal y (the number of dog hours).
y=x+6
Now You plug what y equals into the first equation to solve for x.
9x+8(x+6)=116 Next distribute the 8 to each term.
9x+8(x)+8(6)=116
9x+8x+48=116 Add the like terms together (9x+8x)
17x+48=116 Subtract the 48 from both sides
-48 -48
17x=68 Now divide by 17 on both sides.
______
17 17
x=4 Finally we can take x and plug it back in to one of the equations in order to solve for y. I'm going to choose the second equation.
y=(4)+6
y=10
