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Finding the Fourth Proportional to 388.79, 535.80 and 278.08

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Solution

The fourth proportional to 388.79, 535.80 and 278.08 is: 383.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.79 : 535.80 = 278.08 : x
  2. Step 2: Convert to fraction form
    388.79/535.80 = 278.08/x
  3. Step 3: Cross multiply
    388.79x = 535.80 × 278.08
  4. Step 4: Simplify right side
    388.79x = 148,993.40
  5. Step 5: Solve for x
    x = 148,993.40/388.79
  6. Step 6: Final answer
    x = 383.22

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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.