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Finding the Fourth Proportional to 631.63, 870.70 and 491.50

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Solution

The fourth proportional to 631.63, 870.70 and 491.50 is: 677.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.63 : 870.70 = 491.50 : x
  2. Step 2: Convert to fraction form
    631.63/870.70 = 491.50/x
  3. Step 3: Cross multiply
    631.63x = 870.70 × 491.50
  4. Step 4: Simplify right side
    631.63x = 427,949.83
  5. Step 5: Solve for x
    x = 427,949.83/631.63
  6. Step 6: Final answer
    x = 677.53

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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.