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Finding the Fourth Proportional to 620.88, 931.32 and 312.90

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Solution

The fourth proportional to 620.88, 931.32 and 312.90 is: 469.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.88 : 931.32 = 312.90 : x
  2. Step 2: Convert to fraction form
    620.88/931.32 = 312.90/x
  3. Step 3: Cross multiply
    620.88x = 931.32 × 312.90
  4. Step 4: Simplify right side
    620.88x = 291,410.03
  5. Step 5: Solve for x
    x = 291,410.03/620.88
  6. Step 6: Final answer
    x = 469.35

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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.