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Finding the Fourth Proportional to 669.77, 924.17 and 390.05

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Solution

The fourth proportional to 669.77, 924.17 and 390.05 is: 538.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.77 : 924.17 = 390.05 : x
  2. Step 2: Convert to fraction form
    669.77/924.17 = 390.05/x
  3. Step 3: Cross multiply
    669.77x = 924.17 × 390.05
  4. Step 4: Simplify right side
    669.77x = 360,465.94
  5. Step 5: Solve for x
    x = 360,465.94/669.77
  6. Step 6: Final answer
    x = 538.20

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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.