I believe the answer is B for this question
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:

Step-by-step explanation:
As the triangles are similar :
45/55 = (12x - 3)/143
9/11 = (12x - 3)/143
9 x 13 = 12x - 3
12x = 117 + 3
12x = 120
x = 10
The expression of 25t +45m shows the total number of miles driven at both speeds. In order to solve this equation you would need to know the total number of hours driven in order to multiply that by the appropriate speed in terms of miles per hour.
Answer: 50,380m
Step-by-step explanation:
190m * 270m = 51,300m
23m * 40m = 920m
Because the barn is in the field, we subtract the barn's area from the field's area, which leaves us with
51,300m - 920m = 50,380m