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Finding the Fourth Proportional to 878.00, 1,316.12 and 390.65

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Solution

The fourth proportional to 878.00, 1,316.12 and 390.65 is: 585.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    878.00 : 1,316.12 = 390.65 : x
  2. Step 2: Convert to fraction form
    878.00/1,316.12 = 390.65/x
  3. Step 3: Cross multiply
    878.00x = 1,316.12 × 390.65
  4. Step 4: Simplify right side
    878.00x = 514,133.74
  5. Step 5: Solve for x
    x = 514,133.74/878.00
  6. Step 6: Final answer
    x = 585.58

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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.