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Finding the Fourth Proportional to 690.61, 1,035.32 and 300.31

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Solution

The fourth proportional to 690.61, 1,035.32 and 300.31 is: 450.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.61 : 1,035.32 = 300.31 : x
  2. Step 2: Convert to fraction form
    690.61/1,035.32 = 300.31/x
  3. Step 3: Cross multiply
    690.61x = 1,035.32 × 300.31
  4. Step 4: Simplify right side
    690.61x = 310,916.95
  5. Step 5: Solve for x
    x = 310,916.95/690.61
  6. Step 6: Final answer
    x = 450.21

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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.