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Finding the Fourth Proportional to 702.50, 969.40 and 407.80

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Solution

The fourth proportional to 702.50, 969.40 and 407.80 is: 562.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    702.50 : 969.40 = 407.80 : x
  2. Step 2: Convert to fraction form
    702.50/969.40 = 407.80/x
  3. Step 3: Cross multiply
    702.50x = 969.40 × 407.80
  4. Step 4: Simplify right side
    702.50x = 395,321.32
  5. Step 5: Solve for x
    x = 395,321.32/702.50
  6. Step 6: Final answer
    x = 562.73

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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.