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Finding the Fourth Proportional to 521.45, 719.63 and 311.66

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Solution

The fourth proportional to 521.45, 719.63 and 311.66 is: 430.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.45 : 719.63 = 311.66 : x
  2. Step 2: Convert to fraction form
    521.45/719.63 = 311.66/x
  3. Step 3: Cross multiply
    521.45x = 719.63 × 311.66
  4. Step 4: Simplify right side
    521.45x = 224,282.46
  5. Step 5: Solve for x
    x = 224,282.46/521.45
  6. Step 6: Final answer
    x = 430.11

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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.