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Finding the Fourth Proportional to 669.80, 924.28 and 390.02

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Solution

The fourth proportional to 669.80, 924.28 and 390.02 is: 538.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.80 : 924.28 = 390.02 : x
  2. Step 2: Convert to fraction form
    669.80/924.28 = 390.02/x
  3. Step 3: Cross multiply
    669.80x = 924.28 × 390.02
  4. Step 4: Simplify right side
    669.80x = 360,487.69
  5. Step 5: Solve for x
    x = 360,487.69/669.80
  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.