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Finding the Fourth Proportional to 499.64, 689.30 and 313.05

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Solution

The fourth proportional to 499.64, 689.30 and 313.05 is: 431.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.64 : 689.30 = 313.05 : x
  2. Step 2: Convert to fraction form
    499.64/689.30 = 313.05/x
  3. Step 3: Cross multiply
    499.64x = 689.30 × 313.05
  4. Step 4: Simplify right side
    499.64x = 215,785.37
  5. Step 5: Solve for x
    x = 215,785.37/499.64
  6. Step 6: Final answer
    x = 431.88

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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.