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Finding the Fourth Proportional to 392.80, 540.90 and 282.10

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Solution

The fourth proportional to 392.80, 540.90 and 282.10 is: 388.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    392.80 : 540.90 = 282.10 : x
  2. Step 2: Convert to fraction form
    392.80/540.90 = 282.10/x
  3. Step 3: Cross multiply
    392.80x = 540.90 × 282.10
  4. Step 4: Simplify right side
    392.80x = 152,587.89
  5. Step 5: Solve for x
    x = 152,587.89/392.80
  6. Step 6: Final answer
    x = 388.46

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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.