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Finding the Fourth Proportional to 705.65, 973.62 and 390.87

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Solution

The fourth proportional to 705.65, 973.62 and 390.87 is: 539.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    705.65 : 973.62 = 390.87 : x
  2. Step 2: Convert to fraction form
    705.65/973.62 = 390.87/x
  3. Step 3: Cross multiply
    705.65x = 973.62 × 390.87
  4. Step 4: Simplify right side
    705.65x = 380,558.85
  5. Step 5: Solve for x
    x = 380,558.85/705.65
  6. Step 6: Final answer
    x = 539.31

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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.