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Finding the Fourth Proportional to 642.18, 969.02 and 619.30

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Solution

The fourth proportional to 642.18, 969.02 and 619.30 is: 934.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.18 : 969.02 = 619.30 : x
  2. Step 2: Convert to fraction form
    642.18/969.02 = 619.30/x
  3. Step 3: Cross multiply
    642.18x = 969.02 × 619.30
  4. Step 4: Simplify right side
    642.18x = 600,109.24
  5. Step 5: Solve for x
    x = 600,109.24/642.18
  6. Step 6: Final answer
    x = 934.49

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.