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Finding the Fourth Proportional to 971.50, 1,457.25 and 287.50

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Solution

The fourth proportional to 971.50, 1,457.25 and 287.50 is: 431.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    971.50 : 1,457.25 = 287.50 : x
  2. Step 2: Convert to fraction form
    971.50/1,457.25 = 287.50/x
  3. Step 3: Cross multiply
    971.50x = 1,457.25 × 287.50
  4. Step 4: Simplify right side
    971.50x = 418,959.38
  5. Step 5: Solve for x
    x = 418,959.38/971.50
  6. Step 6: Final answer
    x = 431.25

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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.