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Finding the Fourth Proportional to 669.80, 924.33 and 390.05

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Solution

The fourth proportional to 669.80, 924.33 and 390.05 is: 538.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.80 : 924.33 = 390.05 : x
  2. Step 2: Convert to fraction form
    669.80/924.33 = 390.05/x
  3. Step 3: Cross multiply
    669.80x = 924.33 × 390.05
  4. Step 4: Simplify right side
    669.80x = 360,534.92
  5. Step 5: Solve for x
    x = 360,534.92/669.80
  6. Step 6: Final answer
    x = 538.27

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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.