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Finding the Fourth Proportional to 219.51, 302.80 and 145.80

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Solution

The fourth proportional to 219.51, 302.80 and 145.80 is: 201.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.51 : 302.80 = 145.80 : x
  2. Step 2: Convert to fraction form
    219.51/302.80 = 145.80/x
  3. Step 3: Cross multiply
    219.51x = 302.80 × 145.80
  4. Step 4: Simplify right side
    219.51x = 44,148.24
  5. Step 5: Solve for x
    x = 44,148.24/219.51
  6. Step 6: Final answer
    x = 201.12

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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.