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Finding the Fourth Proportional to 622.80, 859.56 and 390.04

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Solution

The fourth proportional to 622.80, 859.56 and 390.04 is: 538.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    622.80 : 859.56 = 390.04 : x
  2. Step 2: Convert to fraction form
    622.80/859.56 = 390.04/x
  3. Step 3: Cross multiply
    622.80x = 859.56 × 390.04
  4. Step 4: Simplify right side
    622.80x = 335,262.78
  5. Step 5: Solve for x
    x = 335,262.78/622.80
  6. Step 6: Final answer
    x = 538.32

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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.