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Finding the Fourth Proportional to 688.91, 949.42 and 645.06

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Solution

The fourth proportional to 688.91, 949.42 and 645.06 is: 889.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.91 : 949.42 = 645.06 : x
  2. Step 2: Convert to fraction form
    688.91/949.42 = 645.06/x
  3. Step 3: Cross multiply
    688.91x = 949.42 × 645.06
  4. Step 4: Simplify right side
    688.91x = 612,437.23
  5. Step 5: Solve for x
    x = 612,437.23/688.91
  6. Step 6: Final answer
    x = 889.00

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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.