Question

Martha has won 19 out of 28 matches in tennis this season.

2.) Which equation models suggest how many more games she needs to win average 75% wins over loses?

a) 19/28+x=0.75

b) 19+x/28+x=0.75

c) 19/28+x=75

d) 19+x/18+x=75

3.) In order to get college tennis scholarship martha needs to bring her winning average 80% what is the no. of matches she needs to win given that she already won 19 out of 28?

a) 3
b) 4
c) 17
d) 22

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Answer 1

2). A). 19/28 + x = 0.75

Explanation :

28 matches has average of 67.85% which is equals to 68 %

67.85~68%

Now equation for that is 19*x/28 and answer of that will be 67.85

Now here is given how many matches she needs to win in order to win 75 present of over loses it means she has already loses

X-67.85

Now,we have to add 0.75% and we have to make it 0.75 from 68%

In the end

From three main equations it will be

19/28+x=0.75% which is answer a)

3). The answer is simple we have to change 0.75 into 80%

19/28+x=80
19/28=80-x
3/2=80-x

which is equals to 3/2 ~ 3

The answer is a). 3

Answer 2

Given:

The number of matches won by Martha = 19

The total number of matches = 28

To Find:

(1) The equation model that suggests the number of games she needs to win an average of 75% wins over losses.

(2) The number of matches Martha needs to win to get 80%

Solution:

• We will solve this question part-wise using the following steps:

(1)

Step 1: Find the expression for the number of games.

Let the total number of games required to have 75% be y

                            ⇒ y = $\frac{75}{100}$ × 28

                            ⇒ y = 0.75 × 28

Step 2: Find the relation between the total number of games and the number of games required.

• Out of 'y' number of games, Martha has already won 19.

                                      y = 19 + x

So, the required extra number of games is x.

                          ⇒  19 +x = 0.75 × 28

                          ⇒ $\frac{19 + x}{28}$ = 0.75

Thus, the correct option is a) $\frac{19 + x}{28}$ = 0.75

(2)

Step 1: Find the required number of games.

• We need to find 80% of 28.

                                     ⇒ $\frac{80}{100}$ × 28

                                     ⇒ 22.4

                                      ≈ 23

Step 2: Subtract the number of games already won.

• We have to find how many more games Martha needs to win to get to 80%.

                 

• The total number of games to be won = 23

• The number of games Martha has already won = 19
• Therefore, the number of games Martha needs to win = 23-19

                                          = 4

Hence, the correct option is b) 4.

Therefore the answers are:

(1) a) $\frac{19 + x}{28}$ = 0.75

(2) b) 4