ANSWER
The constant of variation is 6.
EXPLANATION
The inverse variation equation is:

We want to find the constant of variation, when x=-3 and y=-2.
We substitute the values for x and y to get,

Multiply out the left hand keeping in mind that negative times negative yields a positive result.
This implies that;

Hence the constant of variation is 6.
Answer:
=11600/3
=3866.66kg
Step-by-step explanation:
dividing the mass with bricks with the three times of the lorry
An equation
what else could it be?
Answer: 6.25^12
Step-by-step explanation:
Let the youngest sister be n years
Lana will be 2n years, as her youngest sister is half her age
The age of the twins separately will be 2n-2 as they are 2 years younger than Lana
So, the equation looks like this:
n + 2n + 2(2n-2) = 45
Now solve for n:
3n + 4n - 4 = 45
7n - 4 = 45
7n = 49
n = 7
So the youngest sister is 7, Lana is 14 and the twins are 12. 14 + 12 + 12 + 7 =45