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Finding the Fourth Proportional to 690.72, 1,035.36 and 348

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Solution

The fourth proportional to 690.72, 1,035.36 and 348 is: 521.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.72 : 1,035.36 = 348 : x
  2. Step 2: Convert to fraction form
    690.72/1,035.36 = 348/x
  3. Step 3: Cross multiply
    690.72x = 1,035.36 × 348
  4. Step 4: Simplify right side
    690.72x = 360,305.28
  5. Step 5: Solve for x
    x = 360,305.28/690.72
  6. Step 6: Final answer
    x = 521.64

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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.