Answer:
a = 12 years
Step-by-step explanation:
Mark is 6 years older than his brother Sam. Now, we are asked to represent Sam’s age by a. This means that if Sam is a years old, Mark is (a + 6) years old.
The sum of their ages is 30, this means that when we add their ages together, we get the sum of thirty.
Mathematically this means a + a + 6 = 30
2a + 6 = 30
This is the equation needed to get a. To get a , we proceed to solve the equation to completion.
2a = 30 - 6
2a = 24
a = 24/2
a = 12
Answer: A) 13
<u>Step-by-step explanation:</u>
Mean - 1 SD: 20.2 - 2.4 = 17.8 --> (18)
Mean + 1 SD: 20.2 + 2.4 = 22.6 --> (23)
Now, find the values on the histogram for 18 through 23:
2 + 3 + 4 + 3 + 1 + 1 = 13
The answer is 3:9 because it says that he sold 3 out of the 12 paintings and so it asks first of how many did he sell and he sold three and how many did he not sell and so it's nine left
The ratio of the amounts is x/24.
The amount invested in company A is unknown. The amount is represented by the variable "x". The amount invested in company B is $24. We need to find out the ratio of the amount invested in company A to that of company B. We need the answer as a fraction.
Let the ratio be represented by the variable "r". A ratio compares two numbers. A ratio expresses how much of one thing there is in comparison to another. A fraction is a portion of a whole or, more broadly, any number of equal pieces. In ordinary English, a fraction denotes the number of components of a specific size.
r = x/24
Hence, the ratio of the amount invested in company A to that of company B is x/24.
To learn more about ratio, visit :
brainly.com/question/13419413
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