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Finding the Fourth Proportional to 256.81, 385.29 and 120.02

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Solution

The fourth proportional to 256.81, 385.29 and 120.02 is: 180.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.81 : 385.29 = 120.02 : x
  2. Step 2: Convert to fraction form
    256.81/385.29 = 120.02/x
  3. Step 3: Cross multiply
    256.81x = 385.29 × 120.02
  4. Step 4: Simplify right side
    256.81x = 46,242.51
  5. Step 5: Solve for x
    x = 46,242.51/256.81
  6. Step 6: Final answer
    x = 180.07

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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.