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Finding the Fourth Proportional to 436.30, 654.48 and 128.20

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Solution

The fourth proportional to 436.30, 654.48 and 128.20 is: 192.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    436.30 : 654.48 = 128.20 : x
  2. Step 2: Convert to fraction form
    436.30/654.48 = 128.20/x
  3. Step 3: Cross multiply
    436.30x = 654.48 × 128.20
  4. Step 4: Simplify right side
    436.30x = 83,904.34
  5. Step 5: Solve for x
    x = 83,904.34/436.30
  6. Step 6: Final answer
    x = 192.31

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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.