10. A bag contains 4 red, 7 blue, 8 green, and 5 white marbles. What is the theoretical
1 answer:
You might be interested in
Answer:
Gina is 12 years old
Step-by-step explanation:
First, we will have to write these statements mathematically and then solve.
Let Gina's age be x, let Gina's brother's age be y and let Gina's sister's age be z.
The second statement"Gina's older sister is twice Gina's age" can be mathematically written as: z =2 x ---------------------------(1)
The next statement "Gina's brother is half Gina's age" can be mathematically written as y = ---------------------------------------(2)
Then the next statement "the sum of their ages is 42" can be mathematically written as: x + y + z = 42 ----------------------------(3)
We can now proceed to solve;
Substitute equation (1) and equation(2) into equation (3)
x + y + z = 42
x + + 2x = 42
Multiply through by 2
2x + x + 4x = 84
7x = 84
Divide both-side of the equation by 7
=
x = 12
Therefore, Gina is 12 years old
Answer:
480 miles.
Step-by-step explanation:
Let x represent the distance between Maria's house and mountains ans r represent Maria's rate for going trip.
We have been given that there was heavy traffic on the way there, and the trip took 12 hours.
We are also told that hen Maya drove home, there was no traffic and the trip only took 8 hours. Maria's average rate was 20 miles per hour faster on the trip home.
So Maria's speed while returning back would be .
Upon equating both distances, we will get:
Upon substituting in equation
, we will get:
Therefore, Maya live 480 miles away from the mountains.