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Finding the Fourth Proportional to 289.80, 435.24 and 145.80

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Solution

The fourth proportional to 289.80, 435.24 and 145.80 is: 218.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.80 : 435.24 = 145.80 : x
  2. Step 2: Convert to fraction form
    289.80/435.24 = 145.80/x
  3. Step 3: Cross multiply
    289.80x = 435.24 × 145.80
  4. Step 4: Simplify right side
    289.80x = 63,457.99
  5. Step 5: Solve for x
    x = 63,457.99/289.80
  6. Step 6: Final answer
    x = 218.97

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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.