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Finding the Fourth Proportional to 518.95, 778.21 and 258.85

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Solution

The fourth proportional to 518.95, 778.21 and 258.85 is: 388.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.95 : 778.21 = 258.85 : x
  2. Step 2: Convert to fraction form
    518.95/778.21 = 258.85/x
  3. Step 3: Cross multiply
    518.95x = 778.21 × 258.85
  4. Step 4: Simplify right side
    518.95x = 201,438.36
  5. Step 5: Solve for x
    x = 201,438.36/518.95
  6. Step 6: Final answer
    x = 388.17

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1.5x scale

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.