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Finding the Fourth Proportional to 631.31, 870.93 and 421.29

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Solution

The fourth proportional to 631.31, 870.93 and 421.29 is: 581.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.31 : 870.93 = 421.29 : x
  2. Step 2: Convert to fraction form
    631.31/870.93 = 421.29/x
  3. Step 3: Cross multiply
    631.31x = 870.93 × 421.29
  4. Step 4: Simplify right side
    631.31x = 366,914.10
  5. Step 5: Solve for x
    x = 366,914.10/631.31
  6. Step 6: Final answer
    x = 581.19

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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.