Ask question

Ask question

All categories

kondor19780726 [428]

3 years ago

12

Lana finished the race in 13.2 seconds . If 84 other girls ran in the event, approximately how many runners did she beat?

1 answer:

BabaBlast [244]3 years ago

6 0

Complete question :

The 100m dah times in the girl's track meet were normally distributed with a mean of 13 seconds and a standard deviation of 0.3 seconds.

Lana finished the race in 13.2 seconds . If 84 other girls ran in the event, approximately how many runners did she beat?

Answer:

21 runners

Step-by-step explanation:

Mean, μ = 13 seconds

Standard deviation, σ = 0.3

Lana's race time = 13.2

We find the proportion of runners who had race time above 13.2 ;

Proportion of who had race tune above 13.2

P(x > 13.2)

Obtain the Zscore

Zscore = (x - μ) / σ

Z = (13.2 - 13) / 0.3

Zscore = 0.2 / 0.3 = 0.6667

P(Z > 0.6667) = 0.25239 (Z probability calculator)

This is about 0.25239 * 100 = 25.24% = 25% (nearest percent)

Hence, Number of runners Lana beat = 25% of total runners ;

0.25 * 84 = 21

Hence, Lana beat about 21 runners

You might be interested in

A rancher has a roll of fencing to enclose a rectangular area. The table shows how the area that the rancher can enclose with th

Free_Kalibri [48]

Checking for each option

Option A: $A(w) = -w^2+200w$

Substitute w = 10 and check if we'd get 900 as the answer
$A(10) = -(10)^2+200(10) = -100+2000 = 1900$

Option B: $A(w) = -w^2+100w$
Substitute w = 10 and check if we'd get 900 as the answer
$A(10)=-(10)^2+100(10)=-100+1000=900$

Option C: $A(w)=w^2+40w$
Substitute w = 10 and check if we'd get 900 as the answer
$A(10) = 10^2+40(10)=100+400=500$

Option D: $A(w) = w^2+90w$
Substitue w = 10 and check if we'd get 900 as the answer
$A(10)=10^2+90(10) = 100+900=1000$

Answer: Option B

8 0

3 years ago

Read 2 more answers

Expression that represent -4 and 6

tensa zangetsu [6.8K]

Answer:

The answer is 3

8 0

2 years ago

Read 2 more answers

Nathaniel works as a baker and makes several batches of muffins every morning. each batch requires 1 1/7 cups of sugar. for a la

kramer

The amount of sugar he will use is 5.22 cups of sugar, and the number of boxes needed to pack the muffins is 13.71 boxes.

<h3>How do we solve a word problem?</h3>

This word problem question can be solved as follows:

Amount of sugar he will use = 1 1/7 * 4 4/7 = 1.142857142857143 * 4.0.571428571428571 = 5.22 cups of sugar

Number of boxes needed to pack the muffins for the meeting = 4 4/7 * 3 = 4.0.571428571428571 * 3 = 13.71 boxes

Learn more about how to solve word problems here: brainly.com/question/13732946.

#SPJ1

8 0

1 year ago

Simplify without exponents.<br> 1/3(3^-2 3^5)

Over [174]

1/3 x (3^-2 x 3^5)
1/3 x (1/3^2 x 243)
1/3 x (1/9 x 243)
1/3 x 27
9

5 0

3 years ago

What is 5 and 3 quarters

liraira [26]

Answer:

In general, 5 and 3 quarters would be 5.75 :)

Remember, there are 4 quarters in $1.00

7 0

2 years ago