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Finding the Fourth Proportional to 690.50, 950.10 and 666.56

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Solution

The fourth proportional to 690.50, 950.10 and 666.56 is: 917.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.50 : 950.10 = 666.56 : x
  2. Step 2: Convert to fraction form
    690.50/950.10 = 666.56/x
  3. Step 3: Cross multiply
    690.50x = 950.10 × 666.56
  4. Step 4: Simplify right side
    690.50x = 633,298.66
  5. Step 5: Solve for x
    x = 633,298.66/690.50
  6. Step 6: Final answer
    x = 917.16

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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.