Here is the link to the graph. You can scale it and tweak it.
https://www.desmos.com/calculator/mawkflj9ws
Hope this helped!
X³ = 125/27
Cube root both sides to isolate the variable:
∛x³ = ∛(125/27)
x = ∛(125/27)
∛125 = 5, ∛27 = 3
x = 5/3
mu = 1100 = population mean
sigma = 275 = population standard deviation
x = 1400 = raw score
z = z score
z = (x-mu)/sigma
z = (1400-1100)/(275)
z = 300/275
z = 1.0909090909091 approximately
z = 1.09
Convention is to round to two decimal places so that you can use a Z table to look up the area under the curve (which helps determine probability).
The positive z score is due to Paula's raw score being above the mean.
This questions can be answered with a calculator, but I have an impression it is meant to be a mental calculation problem, which can be solved as follows.
We know that 10*10=100, in otherwords, √ 100 = 10 which is greater than 9.4247.
We also know that √ 108 is greater than √ 100 =10
So we can conclude that
√ 108 > √ 100 = 10 > 9.4247
or simply
√ 108 > 9.4247
by the transitive property of logical propositions.
If they're integers, that means they can't be fractions (such as 15/2 and 2).
So the only couples of integers that, when multiplied, result in 15 are:
1 and 15
5 and 3.
(there are no other possibilities as both 5 and 3 are not divisible further).
The smaller of the two sums (15+1; 5+3) is 5+3=8.
The least possible sum of a and b is 8.
