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Finding the Fourth Proportional to 991.72, 1,487.06 and 342.30

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Solution

The fourth proportional to 991.72, 1,487.06 and 342.30 is: 513.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    991.72 : 1,487.06 = 342.30 : x
  2. Step 2: Convert to fraction form
    991.72/1,487.06 = 342.30/x
  3. Step 3: Cross multiply
    991.72x = 1,487.06 × 342.30
  4. Step 4: Simplify right side
    991.72x = 509,020.64
  5. Step 5: Solve for x
    x = 509,020.64/991.72
  6. Step 6: Final answer
    x = 513.27

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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.