5. An empty graduated cylinder has a mass of 50 grams. The cylinder has a mass of 120
grams when 30 milliliters of water is poured in. If a rock is added to the graduated
cylinder, then water level rises to 75 milliliters and the mass is now 250 grams. Determine
the density of the rock.

Person A buys 10 granola bars and 6 cups of yogurt for $18

Person B buys 5 granola bars and 4 cups of yogurt for $9.50

Let x represent the granola bars

Let y represent the yogurt

10x + 6y = 18 << ( Divide both sides by 2 )

The second equation is 5x + 4y = 9.50. Now subtract the two equations.

5x + 4y = 9.50

-5x - 3y = -9

         y = $.50

5x + 3(.50) = 9

5x + 1.50 = 9

5x = 7.5

  x = $1.50

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