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Finding the Fourth Proportional to 78.50, 108.23 and 56.63

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Solution

The fourth proportional to 78.50, 108.23 and 56.63 is: 78.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.50 : 108.23 = 56.63 : x
  2. Step 2: Convert to fraction form
    78.50/108.23 = 56.63/x
  3. Step 3: Cross multiply
    78.50x = 108.23 × 56.63
  4. Step 4: Simplify right side
    78.50x = 6,128.24
  5. Step 5: Solve for x
    x = 6,128.24/78.50
  6. Step 6: Final answer
    x = 78.07

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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.