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Bill buys a red marble and a blue marble. If the total weight of 3 such red marbles and 2 such blue marbles is 84g, and the total weight of 12 such red marbles and 5 such blue marbles is 282g, what is weight of the red marble and the blue marble respectively?

User Cope
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2 Answers

5 votes

Final answer:

The weight of the red marble is 16 grams, and the weight of the blue marble is 18 grams, based on the solution of the system of linear equations derived from the given total weights of the marbles.

Step-by-step explanation:

To solve the problem of determining the weight of each marble, we can set up a system of linear equations based on the given information:

Let r be the weight of a red marble in grams.

Let b be the weight of a blue marble in grams.

The total weight of 3 red marbles and 2 blue marbles is 84g.

The total weight of 12 red marbles and 5 blue marbles is 282g.

Based on these statements, we can write two equations:

3r + 2b = 84 (1)

12r + 5b = 282 (2)

We can solve this system of equations by multiplying equation (1) by 4 to eliminate variable b.

(4)(3r + 2b) = (4)(84)

12r + 8b = 336 (3)

Subtract equation (2) from equation (3) to solve for r:

(12r + 8b) - (12r + 5b) = 336 - 282

3b = 54

b = 18 (weight of blue marble)

Substitute value of b in equation (1) to solve for r:

3r + 2(18) = 84

3r + 36 = 84

3r = 48

r = 16 (weight of red marble)

Therefore, the weight of the red marble is 16 grams and the weight of the blue marble is 18 grams.

User Parkash Kumar
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6.9k points
2 votes
approximately it is 17g for each marble
User Taylor Austin
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7.7k points