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Finding the Fourth Proportional to 690.95, 1,035.84 and 280.37

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Solution

The fourth proportional to 690.95, 1,035.84 and 280.37 is: 420.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.95 : 1,035.84 = 280.37 : x
  2. Step 2: Convert to fraction form
    690.95/1,035.84 = 280.37/x
  3. Step 3: Cross multiply
    690.95x = 1,035.84 × 280.37
  4. Step 4: Simplify right side
    690.95x = 290,424.26
  5. Step 5: Solve for x
    x = 290,424.26/690.95
  6. Step 6: Final answer
    x = 420.33

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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.