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Finding the Fourth Proportional to 680.04, 939.30 and 669.80

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Solution

The fourth proportional to 680.04, 939.30 and 669.80 is: 925.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.04 : 939.30 = 669.80 : x
  2. Step 2: Convert to fraction form
    680.04/939.30 = 669.80/x
  3. Step 3: Cross multiply
    680.04x = 939.30 × 669.80
  4. Step 4: Simplify right side
    680.04x = 629,143.14
  5. Step 5: Solve for x
    x = 629,143.14/680.04
  6. Step 6: Final answer
    x = 925.16

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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.