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Finding the Fourth Proportional to 565.20, 780.30 and 388.43

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Solution

The fourth proportional to 565.20, 780.30 and 388.43 is: 536.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    565.20 : 780.30 = 388.43 : x
  2. Step 2: Convert to fraction form
    565.20/780.30 = 388.43/x
  3. Step 3: Cross multiply
    565.20x = 780.30 × 388.43
  4. Step 4: Simplify right side
    565.20x = 303,088.03
  5. Step 5: Solve for x
    x = 303,088.03/565.20
  6. Step 6: Final answer
    x = 536.25

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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.