Answer:
Step-by-step explanation:
The given logarithm is
Let us change to base 3.
The answer is C. You can solve these by plugging in and checking if each equation is true with the given answers. Also, you can solve by using elimination to get one of the variables removed. Then when you have two, two-variable problems, you can solve that system in any of the ways.
Answer:
mean score of class B = 1778/25 = 71.12
Step-by-step explanation:
This was your question : Class A has 12 pupils and class B has 25 pupils. Both classes sit the same maths test. The mean score for class A is 80. The mean score for both classes is 74. What is the mean score (rounded to 2 DP) in the maths test for class B?
mean of class A = Σfx/Σf
mean of class A = 80
Σfx = 80 × 12 = 960
Mean score for both classes = 74
where
b = Σfx of class B
960 + b/37 = 74
cross multiply
960 + b = 2738
b = 2738 - 960
b = 1778
mean score of class B = Σfx/Σf
Σfx = 1778
Σf = 25
Therefore,
1778/25 = 71.12
V = PI x r^2 x H
1348.79 = 3.14 x 5.5^2 x H
1348.79 = 94.985 x h
h = 1348.79 / 94.985
h = 14.2 cm ( round answer if needed)
The answer is C. Just took the quiz and B was wrong. It needs to be the one with the smaller 12.
