To solve for x we proceed as follows:
from the laws of logarithm, given that:
log_a b=c
then
a^c=b
applying the rationale to our question we shall have:
log_5 x=4
hence
5^4=x
x=625
Answer: x=625
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
Based on the amount of your monthly bill, if you lived in England, your bill to the nearest hundredth is $185.82
<h3>How to find your bill in pound sterling?</h3>
You have a monthly bill of $304.72. If this was also your bill in England id you stayed there, it would need to be converted to pounds. The way to do this is by using the exchange rate.
If each British Pound is $1.64 U.S. Dollar, then the value of your monthly bill if you lived in England is:
= Monthly bill in dollars / Conversion or exchange rate
= 304.72 / 1.64
= $185.82
Find out more on the exchange rate at brainly.com/question/20332320
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I think it is the first one could be wrong tho
