Problem 33
For each number, generate a factor tree. This is where you break a number down into smaller factors in a visual "tree" like style. The idea is to factor down to the prime factors and then you circle the common primes between each number. The values you circle are then multiplied if you circle more than one value in each tree.
-------------------------------------------------------------------------------
Problem 34
Xiao factored correctly but didn't pull out the GCF. So he didn't factor fully. In the case of 60 and 90, the GCF is 30. This is the largest shared factor between the two values. So we can pull out 30 to get
60+90 = 30*2+30*3 = 30*(2+3)
I'm basically using the distributive property in reverse. You can distribute the 30 back in and get 60+90 again. Notice how the inner stuff 2 and 3 have no factors in common other than 1.
The answers is A. 60 degrees
Option C: 
is the value of a and b
Explanation:
Given that the expression 
We need to determine the value of a and b
Let us consider the term 
and take the prime factorization of the term 648
Thus, we have,
648 divides by 2,
324 divides by 2,
162 divides by 2,
81 divides by 3,
27 divides by 3,
9 divides by 3,
Thus, we have,
Therefore, equating the powers of 2 and 3, we get,
Hence, the value of a and b is 3 and 4
Thus, Option C is the correct answer.
In addition to mean and sample size you will need the individual scores.
The formula for standard deviation is:
S^2 = E(X-M)^2/N-1
Here's an example:
Data set: 4,4,3,1
Mean: 3
Sample size: 4
First, put the individual scores one after the other and subtract the mean from it.
4 - 3 = 1
4 - 3 = 1
3 - 3 = 0
1 - 3 = -2
Second, square the answers you got from step 1.
1^2 = 1
1^2 = 1
0^2 = 0
-2^2 = 4
Third, plug the values from step 2 into the formula.
S^2 = (1+1+0+4)/(4-1) = 6/3 = 2
Standard deviation = 2
I saw the figure of the fishpond. It composed of a rectangle and a circle. The circle is cut into two and each half is attached to the width of the rectangle making an oblong shaped fishpond.
Length of the rectangle: 2.5 inch
Width of the rectangle and diameter of the circle: 1 inch
1/2 inch equals 15 feet.
2.5 inches = 75 feet
1 inch = 30 feet
Area of a rectangle = 75 ft * 30 ft = 2,250 ft²
Area of a circle = 3.14 * (15ft)² = 3.14 * 225ft² = 706.50 ft²
Total Area = 2,250 ft² + 706.50 ft² = 2,956.50 ft²
