The only other possible meaning I can see is that a2 + b2 means a^2 + b^2. In the case that is a formula that cannot be simplified further, although it could be written as (a + b)^2 - 2ab or (a - b)^2 + 2ab. ... Originally Answered: What is the formula of a2+b2?
To solve for proportion we make use of the z statistic.
The procedure is to solve for the value of the z score and then locate for the
proportion using the standard distribution tables. The formula for z score is:
z = (X – μ) / σ
where X is the sample value, μ is the mean value and σ is
the standard deviation
when X = 70
z1 = (70 – 100) / 15 = -2
Using the standard distribution tables, proportion is P1
= 0.0228
when X = 130
z2 = (130 – 100) /15 = 2
Using the standard distribution tables, proportion is P2
= 0.9772
Therefore the proportion between X of 70 and 130 is:
P (70<X<130) = P2 – P1
P (70<X<130) = 0.9772 - 0.0228
P (70<X<130) = 0.9544
Therefore 0.9544 or 95.44% of the test takers scored
between 70 and 130.
J = 14
J = 1/2S + 4 1/2
14 = 1/2S + 9/2....multiply everything by 2 to get rid of fractions
28 = S + 9
28 - 9 = S
19 = S
check...
14 = 1/2S + 9/2......S = 19
14 = 1/2(19) + 9/2
14 = 9 1/2 + 9/2
14 = 19/2+ 9/2
14 = 28/2
14 = 14 (correct)
so the sister is 19 <===
Their both are even numbers