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Finding the Fourth Proportional to 533.40, 800.76 and 390

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Solution

The fourth proportional to 533.40, 800.76 and 390 is: 585.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    533.40 : 800.76 = 390 : x
  2. Step 2: Convert to fraction form
    533.40/800.76 = 390/x
  3. Step 3: Cross multiply
    533.40x = 800.76 × 390
  4. Step 4: Simplify right side
    533.40x = 312,296.40
  5. Step 5: Solve for x
    x = 312,296.40/533.40
  6. Step 6: Final answer
    x = 585.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.