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Finding the Fourth Proportional to 991.50, 1,487.49 and 307.50

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Solution

The fourth proportional to 991.50, 1,487.49 and 307.50 is: 461.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    991.50 : 1,487.49 = 307.50 : x
  2. Step 2: Convert to fraction form
    991.50/1,487.49 = 307.50/x
  3. Step 3: Cross multiply
    991.50x = 1,487.49 × 307.50
  4. Step 4: Simplify right side
    991.50x = 457,403.18
  5. Step 5: Solve for x
    x = 457,403.18/991.50
  6. Step 6: Final answer
    x = 461.32

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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.