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Finding the Fourth Proportional to 499.16, 687.71 and 394.21

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Solution

The fourth proportional to 499.16, 687.71 and 394.21 is: 543.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.16 : 687.71 = 394.21 : x
  2. Step 2: Convert to fraction form
    499.16/687.71 = 394.21/x
  3. Step 3: Cross multiply
    499.16x = 687.71 × 394.21
  4. Step 4: Simplify right side
    499.16x = 271,102.13
  5. Step 5: Solve for x
    x = 271,102.13/499.16
  6. Step 6: Final answer
    x = 543.12

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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.