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Finding the Fourth Proportional to 631.23, 870.80 and 491.10

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Solution

The fourth proportional to 631.23, 870.80 and 491.10 is: 677.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.23 : 870.80 = 491.10 : x
  2. Step 2: Convert to fraction form
    631.23/870.80 = 491.10/x
  3. Step 3: Cross multiply
    631.23x = 870.80 × 491.10
  4. Step 4: Simplify right side
    631.23x = 427,647.42
  5. Step 5: Solve for x
    x = 427,647.42/631.23
  6. Step 6: Final answer
    x = 677.48

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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.