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:
addie at 4.5 candie bars and frankie had 4
The Volume of cylinder is 3770 cubic millimeters
But, the correct option is not available in options given.
Step-by-step explanation:
Height of cylinder = 3mm
Diameter of cylinder = 40mm
Volume of cylinder = ?
The formula used to find Volume of cylinder is:

Putting values in the formula:
Since we need radius,
radius = diameter/2
radius = 40/2
radius = 20 mm
So,

The Volume of cylinder is 3770 cubic millimeters
But, the correct option is not available in options given.
Keywords: Volume of cylinder
Learn more about Volume of cylinder at:
#learnwithBrainly
Four hundred twenty-three billion, ninety million, seven hundred nine thousand
Hope this helped:))