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Finding the Fourth Proportional to 705.53, 973.69 and 390.87

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Solution

The fourth proportional to 705.53, 973.69 and 390.87 is: 539.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    705.53 : 973.69 = 390.87 : x
  2. Step 2: Convert to fraction form
    705.53/973.69 = 390.87/x
  3. Step 3: Cross multiply
    705.53x = 973.69 × 390.87
  4. Step 4: Simplify right side
    705.53x = 380,586.21
  5. Step 5: Solve for x
    x = 380,586.21/705.53
  6. Step 6: Final answer
    x = 539.43

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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.