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Finding the Fourth Proportional to 656.90, 985.47 and 291.70

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Solution

The fourth proportional to 656.90, 985.47 and 291.70 is: 437.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.90 : 985.47 = 291.70 : x
  2. Step 2: Convert to fraction form
    656.90/985.47 = 291.70/x
  3. Step 3: Cross multiply
    656.90x = 985.47 × 291.70
  4. Step 4: Simplify right side
    656.90x = 287,461.60
  5. Step 5: Solve for x
    x = 287,461.60/656.90
  6. Step 6: Final answer
    x = 437.60

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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.