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Finding the Fourth Proportional to 56.55, 78 and 39.08

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Solution

The fourth proportional to 56.55, 78 and 39.08 is: 53.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    56.55 : 78 = 39.08 : x
  2. Step 2: Convert to fraction form
    56.55/78 = 39.08/x
  3. Step 3: Cross multiply
    56.55x = 78 × 39.08
  4. Step 4: Simplify right side
    56.55x = 3,048.24
  5. Step 5: Solve for x
    x = 3,048.24/56.55
  6. Step 6: Final answer
    x = 53.90

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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.