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Finding the Fourth Proportional to 681.95, 1,020.80 and 507.60

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Solution

The fourth proportional to 681.95, 1,020.80 and 507.60 is: 759.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.95 : 1,020.80 = 507.60 : x
  2. Step 2: Convert to fraction form
    681.95/1,020.80 = 507.60/x
  3. Step 3: Cross multiply
    681.95x = 1,020.80 × 507.60
  4. Step 4: Simplify right side
    681.95x = 518,159.35
  5. Step 5: Solve for x
    x = 518,159.35/681.95
  6. Step 6: Final answer
    x = 759.82

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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.