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Finding the Fourth Proportional to 642.41, 885.71 and 421.01

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Solution

The fourth proportional to 642.41, 885.71 and 421.01 is: 580.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.41 : 885.71 = 421.01 : x
  2. Step 2: Convert to fraction form
    642.41/885.71 = 421.01/x
  3. Step 3: Cross multiply
    642.41x = 885.71 × 421.01
  4. Step 4: Simplify right side
    642.41x = 372,886.23
  5. Step 5: Solve for x
    x = 372,886.23/642.41
  6. Step 6: Final answer
    x = 580.45

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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.