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Finding the Fourth Proportional to 647.76, 971.80 and 191.76

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Solution

The fourth proportional to 647.76, 971.80 and 191.76 is: 287.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.76 : 971.80 = 191.76 : x
  2. Step 2: Convert to fraction form
    647.76/971.80 = 191.76/x
  3. Step 3: Cross multiply
    647.76x = 971.80 × 191.76
  4. Step 4: Simplify right side
    647.76x = 186,352.37
  5. Step 5: Solve for x
    x = 186,352.37/647.76
  6. Step 6: Final answer
    x = 287.69

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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.