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Finding the Fourth Proportional to 642.21, 962.77 and 312.70

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Solution

The fourth proportional to 642.21, 962.77 and 312.70 is: 468.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.21 : 962.77 = 312.70 : x
  2. Step 2: Convert to fraction form
    642.21/962.77 = 312.70/x
  3. Step 3: Cross multiply
    642.21x = 962.77 × 312.70
  4. Step 4: Simplify right side
    642.21x = 301,052.00
  5. Step 5: Solve for x
    x = 301,052.00/642.21
  6. Step 6: Final answer
    x = 468.77

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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.