1.John’s age is three times that of his sister. When you add John’s age to his sister's age, you get 36. How old are John and his sister? (a)Write an equation that represents the situation. (1 point)
(b)Solve the equation from Part (a). Show your work. (3 points)


Part A: Write an equation.
If the present age is y, then n times the present age = ny.
If the present age is x, then age n years later/hence = x + n.
If the present age is x, then age n years ago = x – n.
The ages in a ratio a: b will be ax and bx.

Part B: Solve the equation.

John’s age =

John’s sister’s age =

sister = 6 years

John=18 years

Step-by-step explanation:

A(S) + 12 = 3 * A(S), subtracting A(S) from both sides one gets 12 = 2 * A(S). Now dividing both sides by 2 we get A(S) = 12/2 = 6 . Therefore, the age of the sister is 6 years when her brother John is three times as old, that is 18 years.

36-x=y

y*3=x

x+y=36

Step-by-step explanation:

I wasnt really sure how to write the equation the way you're supposesd to?

John is 27 and his sister is 9. 9*3=27

I just used guess and check sorry

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.