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Finding the Fourth Proportional to 540.40, 745.78 and 319.30

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Solution

The fourth proportional to 540.40, 745.78 and 319.30 is: 440.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.40 : 745.78 = 319.30 : x
  2. Step 2: Convert to fraction form
    540.40/745.78 = 319.30/x
  3. Step 3: Cross multiply
    540.40x = 745.78 × 319.30
  4. Step 4: Simplify right side
    540.40x = 238,127.55
  5. Step 5: Solve for x
    x = 238,127.55/540.40
  6. Step 6: Final answer
    x = 440.65

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1.5x scale

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.