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Finding the Fourth Proportional to 630.65, 871.13 and 485.08

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Solution

The fourth proportional to 630.65, 871.13 and 485.08 is: 670.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.65 : 871.13 = 485.08 : x
  2. Step 2: Convert to fraction form
    630.65/871.13 = 485.08/x
  3. Step 3: Cross multiply
    630.65x = 871.13 × 485.08
  4. Step 4: Simplify right side
    630.65x = 422,566.78
  5. Step 5: Solve for x
    x = 422,566.78/630.65
  6. Step 6: Final answer
    x = 670.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.