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Finding the Fourth Proportional to 305.05, 420.98 and 188.68

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Solution

The fourth proportional to 305.05, 420.98 and 188.68 is: 260.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.05 : 420.98 = 188.68 : x
  2. Step 2: Convert to fraction form
    305.05/420.98 = 188.68/x
  3. Step 3: Cross multiply
    305.05x = 420.98 × 188.68
  4. Step 4: Simplify right side
    305.05x = 79,430.51
  5. Step 5: Solve for x
    x = 79,430.51/305.05
  6. Step 6: Final answer
    x = 260.39

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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.