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Finding the Fourth Proportional to 305.01, 420.39 and 258.51

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Solution

The fourth proportional to 305.01, 420.39 and 258.51 is: 356.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.01 : 420.39 = 258.51 : x
  2. Step 2: Convert to fraction form
    305.01/420.39 = 258.51/x
  3. Step 3: Cross multiply
    305.01x = 420.39 × 258.51
  4. Step 4: Simplify right side
    305.01x = 108,675.02
  5. Step 5: Solve for x
    x = 108,675.02/305.01
  6. Step 6: Final answer
    x = 356.30

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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.