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Finding the Fourth Proportional to 639.90, 953.04 and 617.22

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Solution

The fourth proportional to 639.90, 953.04 and 617.22 is: 919.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.90 : 953.04 = 617.22 : x
  2. Step 2: Convert to fraction form
    639.90/953.04 = 617.22/x
  3. Step 3: Cross multiply
    639.90x = 953.04 × 617.22
  4. Step 4: Simplify right side
    639.90x = 588,232.26
  5. Step 5: Solve for x
    x = 588,232.26/639.90
  6. Step 6: Final answer
    x = 919.26

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.