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Finding the Fourth Proportional to 475.19, 712.80 and 128.51

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Solution

The fourth proportional to 475.19, 712.80 and 128.51 is: 192.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    475.19 : 712.80 = 128.51 : x
  2. Step 2: Convert to fraction form
    475.19/712.80 = 128.51/x
  3. Step 3: Cross multiply
    475.19x = 712.80 × 128.51
  4. Step 4: Simplify right side
    475.19x = 91,603.04
  5. Step 5: Solve for x
    x = 91,603.04/475.19
  6. Step 6: Final answer
    x = 192.77

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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.