Answer:
Rock A had a weight of 0.33Kg
Step-by-step explanation:
Let X: the weight of rock A and Y: the weight of rock B. The information available suggests that:
X + Y = 3.3 [Eq. one]
X = 0.1 (X + Y) [Eq. two]
Considering equation 2, we have that X = 0.1X + 0.1Y, which produces:
0.9X = 0.1Y ------------> 9X = Y. Substituting this last result in equation 1, you have:
X + 9X = 3.3, that is,
10X = 3.3 --------> X = 3.3 / 10 = 0.33Kg. As Y = 9X, then, Y = 9 (0.33) = 2.97Kg
