Answer:
The cost price of the watch was rs 239.4
Step-by-step explanation:
252 * 0.05 = 12.6
252 - 12.6 = 239.4
Hope this helps.
Her speed was 62.5 miles per hour.
75% = 3/4
3/4 of 180 = 135
Answer:
And if we solve for a we got
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the hourly rates of a population, and for this case we know the distribution for X is given by:
For this part we want to find a value a, such that we satisfy this condition:
(a)
(b)
Both conditions are equivalent on this case. We can use the z score again in order to find the value a.
As we can see on the figure attached the z value that satisfy the condition with 0.80 of the area on the left and 0.20 of the area on the right it's z=0.842. On this case P(Z<0.842)=0.8 and P(z>0.842)=0.20
If we use condition (b) from previous we have this:
But we know which value of z satisfy the previous equation so then we can do this:
And if we solve for a we got
Answer:
Step-by-step explanation:
(2b+-7)+5(b+-3)
Multiply 5 throughout the second parentheses
(2b-7)+(5b-15)
Add 2b and 5b
7b-7-15
Subtract -7 and -15
7b-22