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Finding the Fourth Proportional to 405.90, 560.28 and 258.66

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Solution

The fourth proportional to 405.90, 560.28 and 258.66 is: 357.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.90 : 560.28 = 258.66 : x
  2. Step 2: Convert to fraction form
    405.90/560.28 = 258.66/x
  3. Step 3: Cross multiply
    405.90x = 560.28 × 258.66
  4. Step 4: Simplify right side
    405.90x = 144,922.02
  5. Step 5: Solve for x
    x = 144,922.02/405.90
  6. Step 6: Final answer
    x = 357.04

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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.