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Finding the Fourth Proportional to 347.21, 520.77 and 90.71

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Solution

The fourth proportional to 347.21, 520.77 and 90.71 is: 136.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    347.21 : 520.77 = 90.71 : x
  2. Step 2: Convert to fraction form
    347.21/520.77 = 90.71/x
  3. Step 3: Cross multiply
    347.21x = 520.77 × 90.71
  4. Step 4: Simplify right side
    347.21x = 47,239.05
  5. Step 5: Solve for x
    x = 47,239.05/347.21
  6. Step 6: Final answer
    x = 136.05

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.