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2 years ago

Deanna gets 3 problems incorrect on her math quiz and scores 85%. How many questions were on the quiz?

Mathematics

1 answer:

katrin2010 [14]2 years ago

5 0

Answer:

There were 20 questions on the quiz

Step-by-step explanation:

In this question, we are concerned with knowing the number of questions on a quiz, given that Deana had a certain percentage after scoring an amount of marks.

We proceed as follows;

Let the number of questions on the quiz be X.

Now, she got 85% by making 3 incorrect choices. This means the percentage of questions she got incorrectly would be 100-85 = 15%

what we are saying is that it is just 15% of her questions that were wrong.

This mathematically;

15% of x = 3

15/100 * x = 3

15x = 3 * 100

15x = 300

x = 300/15

x = 20

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2. (15 points) Shelly has a photo that is 7 1/3 inches tall. She wants to shrink it down to fit in a picture frame that is only

Inessa [10]

A. Which reduction should she use so the picture fills as much of the frame as possible, without being too large?

Find the scale factor to get rom 7 1/3 inches to 5 1/3 inches:

5 1/3 / 7 1/3 = 0.7272

Now rewrite the fraction as decimals:

2/3 = 0.667

¾ = 0.75

5/9 = 0.555

The closest scale that would still fit the frame would be 2/3 because it is under 0.727.

B. How much extra space is there in the frame when she uses the reduction from Part A?

Multiply the original size by the scale factor to use:

7 1/3 x 2/3 = 4 8/9

Now subtract the scaled size from the original size:

7 1/3 – 4 8/9 = 2 4/9 inches extra

C. If she had a machine that could reduce by any amount, so that she could make the reduced picture fit in the frame exactly, what fraction would the reduction be?

Convert the scale from part A to a fraction:

0.72 = 72/99 which reduces to 8/11

5 0

2 years ago

Need help with math problem give 5 stars and a good rating

slavikrds [6]

Answer:

B,C,D

Step-by-step explanation:

24ft =288 in A IS FALSE

2 miles = 10560 ft B IS TRUE

1/2 miles = 2640 ft C IS TRUE

0.5 miles = 880 Yds D IS TRUE

0.5 ft = 6 in E IS FALSE

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2 years ago

Which zero pair could be added to the function fon) = x2 + 12x + 6 so that the function can be written in vertex form?

Oksanka [162]

ANSWER

36,-36

EXPLANATION

The given function is:

$f(x) = {x}^{2} + 12x + 6$

To write this function in vertex form;

We need to add and subtract the square of half the coefficient of x.

The coefficient of x is 12.

Half of it is 6.

The square of 6 is 36.

Therefore we add and subtract 36.

Hence the zero pair is:

36, -36.

The correct answer is D.

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2 years ago

Read 2 more answers

Sam kept track of the number of problems he was assigned for his math homework on the box plot.

yulyashka [42]

Answer:

Statement A is correct about Sam's box and whisker plot.

Step-by-step explanation:

We have been given a box plot and we are asked to find out true statement according to the box plot.

Since we know data represented by box plot is divided in four equal parts.

Upon looking at our box plot we can see that our data is symmetric. It's median is 15, which means half the math assignments have less than 15 problems and half of the math assignments have more than 15 problems.

Interquartile range represents 50% values of data and it is the difference between upper quartile and lower quartile. IQR is not affected by outliers.

$IQR=Q_3-Q_1$