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Finding the Fourth Proportional to 690.78, 953.26 and 380.28

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Solution

The fourth proportional to 690.78, 953.26 and 380.28 is: 524.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.78 : 953.26 = 380.28 : x
  2. Step 2: Convert to fraction form
    690.78/953.26 = 380.28/x
  3. Step 3: Cross multiply
    690.78x = 953.26 × 380.28
  4. Step 4: Simplify right side
    690.78x = 362,505.71
  5. Step 5: Solve for x
    x = 362,505.71/690.78
  6. Step 6: Final answer
    x = 524.78

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.