Unit 6 · Algebra
Blocks and Spheres in a Jug — Find the Water Level
Lesson 22 of 24
About this lesson
Each row in the table is a hidden equation: water level = starting water + volume of objects submerged. Subtract pairs of rows to eliminate unknowns one at a time until you find each object's volume.
Chapters
Question
Elin has a measuring jug containing some water.
She also has some identical blocks and some identical spheres. They sink in water.
Elin puts some of these objects in the jug and reads the level of the water. She writes the results in this table:
| Objects under the water | Level of water in the jug |
|---|---|
| 2 blocks | 54 mL |
| 1 block and 3 spheres | 54 mL |
| 3 blocks and 3 spheres | 66 mL |
| 1 block and 1 sphere | ? |
What is the level of the water when 1 block and 1 sphere are under the water?
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