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Finding the Fourth Proportional to 686.68, 1,030 and 275.70

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Solution

The fourth proportional to 686.68, 1,030 and 275.70 is: 413.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.68 : 1,030 = 275.70 : x
  2. Step 2: Convert to fraction form
    686.68/1,030 = 275.70/x
  3. Step 3: Cross multiply
    686.68x = 1,030 × 275.70
  4. Step 4: Simplify right side
    686.68x = 283,971
  5. Step 5: Solve for x
    x = 283,971/686.68
  6. Step 6: Final answer
    x = 413.54

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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.