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Finding the Fourth Proportional to 77.51, 106.85 and 56.76

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Solution

The fourth proportional to 77.51, 106.85 and 56.76 is: 78.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.51 : 106.85 = 56.76 : x
  2. Step 2: Convert to fraction form
    77.51/106.85 = 56.76/x
  3. Step 3: Cross multiply
    77.51x = 106.85 × 56.76
  4. Step 4: Simplify right side
    77.51x = 6,064.81
  5. Step 5: Solve for x
    x = 6,064.81/77.51
  6. Step 6: Final answer
    x = 78.25

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Find fourth proportional to 38.76, 53.43 and 28.38
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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.