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Finding the Fourth Proportional to 420.06, 628.89 and 291.42

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Solution

The fourth proportional to 420.06, 628.89 and 291.42 is: 436.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.06 : 628.89 = 291.42 : x
  2. Step 2: Convert to fraction form
    420.06/628.89 = 291.42/x
  3. Step 3: Cross multiply
    420.06x = 628.89 × 291.42
  4. Step 4: Simplify right side
    420.06x = 183,271.12
  5. Step 5: Solve for x
    x = 183,271.12/420.06
  6. Step 6: Final answer
    x = 436.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.