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Finding the Fourth Proportional to 660.80, 909.60 and 603.20

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Solution

The fourth proportional to 660.80, 909.60 and 603.20 is: 830.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.80 : 909.60 = 603.20 : x
  2. Step 2: Convert to fraction form
    660.80/909.60 = 603.20/x
  3. Step 3: Cross multiply
    660.80x = 909.60 × 603.20
  4. Step 4: Simplify right side
    660.80x = 548,670.72
  5. Step 5: Solve for x
    x = 548,670.72/660.80
  6. Step 6: Final answer
    x = 830.31

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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.