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Finding the Fourth Proportional to 521.60, 719.68 and 311.80

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Solution

The fourth proportional to 521.60, 719.68 and 311.80 is: 430.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.60 : 719.68 = 311.80 : x
  2. Step 2: Convert to fraction form
    521.60/719.68 = 311.80/x
  3. Step 3: Cross multiply
    521.60x = 719.68 × 311.80
  4. Step 4: Simplify right side
    521.60x = 224,396.22
  5. Step 5: Solve for x
    x = 224,396.22/521.60
  6. Step 6: Final answer
    x = 430.21

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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.