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Finding the Fourth Proportional to 399.90, 552.30 and 380.46

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Solution

The fourth proportional to 399.90, 552.30 and 380.46 is: 525.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.90 : 552.30 = 380.46 : x
  2. Step 2: Convert to fraction form
    399.90/552.30 = 380.46/x
  3. Step 3: Cross multiply
    399.90x = 552.30 × 380.46
  4. Step 4: Simplify right side
    399.90x = 210,128.06
  5. Step 5: Solve for x
    x = 210,128.06/399.90
  6. Step 6: Final answer
    x = 525.45

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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.