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Finding the Fourth Proportional to 642.36, 886.88 and 445.80

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Solution

The fourth proportional to 642.36, 886.88 and 445.80 is: 615.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.36 : 886.88 = 445.80 : x
  2. Step 2: Convert to fraction form
    642.36/886.88 = 445.80/x
  3. Step 3: Cross multiply
    642.36x = 886.88 × 445.80
  4. Step 4: Simplify right side
    642.36x = 395,371.10
  5. Step 5: Solve for x
    x = 395,371.10/642.36
  6. Step 6: Final answer
    x = 615.50

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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.