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Finding the Fourth Proportional to 631.16, 948.78 and 389.21

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Solution

The fourth proportional to 631.16, 948.78 and 389.21 is: 585.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.16 : 948.78 = 389.21 : x
  2. Step 2: Convert to fraction form
    631.16/948.78 = 389.21/x
  3. Step 3: Cross multiply
    631.16x = 948.78 × 389.21
  4. Step 4: Simplify right side
    631.16x = 369,269.92
  5. Step 5: Solve for x
    x = 369,269.92/631.16
  6. Step 6: Final answer
    x = 585.07

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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.