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Finding the Fourth Proportional to 705.18, 970.94 and 640.38

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Solution

The fourth proportional to 705.18, 970.94 and 640.38 is: 881.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    705.18 : 970.94 = 640.38 : x
  2. Step 2: Convert to fraction form
    705.18/970.94 = 640.38/x
  3. Step 3: Cross multiply
    705.18x = 970.94 × 640.38
  4. Step 4: Simplify right side
    705.18x = 621,770.56
  5. Step 5: Solve for x
    x = 621,770.56/705.18
  6. Step 6: Final answer
    x = 881.72

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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.