The answer is c be us wit is goin up by 3.5/1
Is this all the problem wants ?
Answer:
See explaination
Step-by-step explanation:
We can define standard deviation in statistics as a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean of the set, while a high standard deviation indicates that the values are spread out over a wider range.
See attachment for the step by step solution
Let Sydney's age be x
Christine's age is 2x
Sum of their age is 54
x + 2x = 54
3x = 54
x = 18
Sydney is 18 years old.