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Finding the Fourth Proportional to 978.10, 1,349.78 and 536

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Solution

The fourth proportional to 978.10, 1,349.78 and 536 is: 739.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    978.10 : 1,349.78 = 536 : x
  2. Step 2: Convert to fraction form
    978.10/1,349.78 = 536/x
  3. Step 3: Cross multiply
    978.10x = 1,349.78 × 536
  4. Step 4: Simplify right side
    978.10x = 723,482.08
  5. Step 5: Solve for x
    x = 723,482.08/978.10
  6. Step 6: Final answer
    x = 739.68

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.