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Finding the Fourth Proportional to 1,998.85, 2,998.28 and 612.20

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Solution

The fourth proportional to 1,998.85, 2,998.28 and 612.20 is: 918.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,998.85 : 2,998.28 = 612.20 : x
  2. Step 2: Convert to fraction form
    1,998.85/2,998.28 = 612.20/x
  3. Step 3: Cross multiply
    1,998.85x = 2,998.28 × 612.20
  4. Step 4: Simplify right side
    1,998.85x = 1,835,547.02
  5. Step 5: Solve for x
    x = 1,835,547.02/1,998.85
  6. Step 6: Final answer
    x = 918.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.