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Finding the Fourth Proportional to 621.12, 931.76 and 210.15

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Solution

The fourth proportional to 621.12, 931.76 and 210.15 is: 315.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.12 : 931.76 = 210.15 : x
  2. Step 2: Convert to fraction form
    621.12/931.76 = 210.15/x
  3. Step 3: Cross multiply
    621.12x = 931.76 × 210.15
  4. Step 4: Simplify right side
    621.12x = 195,808.31
  5. Step 5: Solve for x
    x = 195,808.31/621.12
  6. Step 6: Final answer
    x = 315.25

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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.