I need help to do this

When servicing a heating boiler and radiators, a plumer knows that the time he will take is given by the formula

Allushta [10]

Answer:

£110

Step-by-step explanation:

We know how much time it takes for a boiler and a radiator, and we need to know how much it will cost for 1 boiler and 4 radiators. We have an initial cost of £30, and since hes doing a boiler - which we know takes an hour - we can already add £20 for a start of £50.

Now, there are 4 radiators, that take 45 minutes each. We need to use this equation:

$(45*4)/60$

We divide by 60 because there are 60 minutes in an hour, and he charges by hour. So:

$180/60=3$

Now, to find out how much to charge, we need to figure out how much to add to the £50. Since it's £20 an hour, and it takes 3 hours to do the 4 radiators, we need to multiply:

$3*20=60$

Now we add our totals for a grand total of...

$50+60=110$

6 0

3 years ago

A principal of $2900 is invested at 4.25% interest, compounded annually. How much will the investment be worth after 7 years?

olga2289 [7]

Let S = Sum after 13 years

So = amount invested

t = time in years

i = annual interest rate = .0325

The S = So(1+i)t = $2,200(1.0325)13 = $3,334.21

4 0

2 years ago

Billy makes $5 a week in allowance plus $4 for each lawn that he mows.

Ad libitum [116K]

Answer:

$15 < $4n + $5

Step-by-step explanation:

We know that Billy needs to make more than $15 between his allowance and the lawns that he mows. This means our inequality should include $15<. Also, since Billy will make $4 per lawn, that means we need to multiply $4 by the number of lawns he needs to mow, n: $4n. So far we have the following: $15<$4n. Next, we know that he makes $5 each week, on top of what he makes mowing each law. This means we need to add the $5 to the $4n. When we put all of these pieces together, we will get the following inequality: $15<$4n+$5

7 0

3 years ago

The area of a square is 72.25 inches squared. Find the length of the side and the perimeter.

Nadya [2.5K]

Answer:

8.5 inches and 34 inches

Step-by-step explanation:

Area of the square = 72.25

side² = 72.25

side = \sqrt{72.25}

Side = 8.5 in

Perimeter = 4 × side

Perimeter = 4 × 8.5 in

Perimeter = 34 in

6 0

3 years ago

Write the slope intercept form of the r question of the line parallel to the graph of 2x+y=5 that passes through (0,1)

Fofino [41]

Step-by-step explanation:

first let's get the original line in slope intercept form.

the vegetal slope intercept form is

y = ax + b

a is the slope, b is the y-intercept.

2x + y = 5

y = -2x + 5

there !

a line parallel to this line must have the same slope (-2).

but it will intersect with the y-axis at a different point.

the y-intersect is the y value when x = 0.

the given point (0, 1) is already that y-intersect (because x=0).

so, the desired parallel line function is

y = -2x + 1

if we had a different point of the line, e.g. (4, -7), we would go back to the general equation

y = ax + b

put in the slope we know (-2)

y = -2x + b

and then put in the x and y cakes if the point and calculate b

-7 = -2×4 + b

-7 = -8 + b

b = 1

and then we get again

y = -2x + 1

4 0

2 years ago