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Finding the Fourth Proportional to 661.64, 912.92 and 378.02

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Solution

The fourth proportional to 661.64, 912.92 and 378.02 is: 521.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.64 : 912.92 = 378.02 : x
  2. Step 2: Convert to fraction form
    661.64/912.92 = 378.02/x
  3. Step 3: Cross multiply
    661.64x = 912.92 × 378.02
  4. Step 4: Simplify right side
    661.64x = 345,099.40
  5. Step 5: Solve for x
    x = 345,099.40/661.64
  6. Step 6: Final answer
    x = 521.58

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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.