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Finding the Fourth Proportional to 665.79, 918.47 and 565.80

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Solution

The fourth proportional to 665.79, 918.47 and 565.80 is: 780.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.79 : 918.47 = 565.80 : x
  2. Step 2: Convert to fraction form
    665.79/918.47 = 565.80/x
  3. Step 3: Cross multiply
    665.79x = 918.47 × 565.80
  4. Step 4: Simplify right side
    665.79x = 519,667.50
  5. Step 5: Solve for x
    x = 519,667.50/665.79
  6. Step 6: Final answer
    x = 780.53

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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.