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Finding the Fourth Proportional to 499.86, 689.72 and 290.05

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Solution

The fourth proportional to 499.86, 689.72 and 290.05 is: 400.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.86 : 689.72 = 290.05 : x
  2. Step 2: Convert to fraction form
    499.86/689.72 = 290.05/x
  3. Step 3: Cross multiply
    499.86x = 689.72 × 290.05
  4. Step 4: Simplify right side
    499.86x = 200,050.11
  5. Step 5: Solve for x
    x = 200,050.11/499.86
  6. Step 6: Final answer
    x = 400.21

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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.