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Finding the Fourth Proportional to 386.40, 579.70 and 155.32

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Solution

The fourth proportional to 386.40, 579.70 and 155.32 is: 233.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.40 : 579.70 = 155.32 : x
  2. Step 2: Convert to fraction form
    386.40/579.70 = 155.32/x
  3. Step 3: Cross multiply
    386.40x = 579.70 × 155.32
  4. Step 4: Simplify right side
    386.40x = 90,039.00
  5. Step 5: Solve for x
    x = 90,039.00/386.40
  6. Step 6: Final answer
    x = 233.02

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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.