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Finding the Fourth Proportional to 971.88, 1,341.30 and 640.50

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Solution

The fourth proportional to 971.88, 1,341.30 and 640.50 is: 883.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    971.88 : 1,341.30 = 640.50 : x
  2. Step 2: Convert to fraction form
    971.88/1,341.30 = 640.50/x
  3. Step 3: Cross multiply
    971.88x = 1,341.30 × 640.50
  4. Step 4: Simplify right side
    971.88x = 859,102.65
  5. Step 5: Solve for x
    x = 859,102.65/971.88
  6. Step 6: Final answer
    x = 883.96

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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.