There are 12 inches in one foot, creating the equation y=12x If a door frame is 5.75 feet tall, how many inches tall is it?

A high school mathematics teacher can grade a set of exams in 7 hours working alone. If their student teacher helps them, it wi

Stels [109]

It takes 9 hrs 19.8 minutes for the student teacher to grade the exams if they worked alone

Solution:

Let the efficiency of the school teacher be “x” and the efficiency of the student teacher be “y”

Here the word efficiency means the rate of doing work

Let the total work to be completed be W

According to the question,

The time taken by the school teacher to complete the work is 7 hrs.

So we can write it in equation form

$W = x \times 7$ ---- eqn 1

where W is the total work and x is the efficiency

Similarly for student teacher and school teacher doing the work simultaneously, we can write the equation as

$W =(x +y ) \times 4$

Equating eqn 1 and 2

$x \times 7=(x+y) \times 4$

7x = 4x + 4y

3x = 4y

So in ratio x : y = 4 : 3

Now putting value of x = 4 in equation (1) we get total work to be 28

Now, total time taken by the student teacher = total work ÷ efficiency of student teacher

Hence, total time taken by the student teacher = 28 ÷ 3 = 9.33 hrs

= 9 hrs 19.8 minutes

Hence it takes 9 hrs 19.8 minutes for the student teacher to grade the exams if they worked alone

4 0

3 years ago

Can you convert radians to degrees by replacing pi with 180

olchik [2.2K]

can you convert radians to degrees by replacing pi with 180

yes

7 0

3 years ago

Sumalee won 40 super bouncy balls playing horseshoes at her schools game last night. Later, she gave two to each of her friends.

Lina20 [59]

Before jumping into doing this problem, it is important to look at all the information's that have been made available in the question. Based on those given conditions the answer to the problem can be easily deduced.
Let us assume the number of friends Sumalee has = x
Then
2x + 8 = 40
2x = 40 -8
2x = 32
x = 32/2
x = 16
So Sumalee has 16 friends. There are numerous ways to get to the answer that is required to be found. This is the easiest and the shortest method. Hope i helped you.

6 0

3 years ago

Read 2 more answers

Please help i will give brainly :

Lubov Fominskaja [6]

1) The x-axis represents the energy ( $E$ ), in joules. The y-axis represents the amplitude ( $x$ ), in milimeters.

2) The curve depicts an monotonous decrecent rate of change.

3) The amplitude is directly proportional to the root square of the energy.

<h3>How to analyze a graph relationship between two variables</h3>

In this question we have a relationship between two variables, in which we must apply principles of functional analysis to respond three questions presented in the statement.

Now we proceed to answer the three questions below:

What is on the x-axis? The y-axis? R/ The x-axis represents the energy ( $E$ ), in joules. The y-axis represents the amplitude ( $x$ ), in milimeters.
How would you describe the rate of change of the line? R/ The curve depicts an monotonous decrecent rate of change, that is, the slope converges to zero when the energy tends to infinite.
What does this tell you about the relationship between amplitude and energy? R/ The curve show a strong similarity with a function of the form $x = A\cdot \sqrt{E}$ . Hence, the amplitude is directly proportional to the root square of the energy.

To learn more on functions, we kindly invite to check this verified question: brainly.com/question/12431044

5 0

2 years ago

How do percents show the relationship between quantities?

Alik [6]

Answer: Decide whether two quantities are in a proportional relationship, by testing for equivalent ratios in a table or graphing on a coordinate plane and observing whether the graph is a straight line through the origin . Use proportional relationships to solve multistep ratio and percent problems.

Step-by-step explanation:

6 0

3 years ago