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Finding the Fourth Proportional to 1,415.00, 2,120.19 and 720.71

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Solution

The fourth proportional to 1,415.00, 2,120.19 and 720.71 is: 1,079.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,415.00 : 2,120.19 = 720.71 : x
  2. Step 2: Convert to fraction form
    1,415.00/2,120.19 = 720.71/x
  3. Step 3: Cross multiply
    1,415.00x = 2,120.19 × 720.71
  4. Step 4: Simplify right side
    1,415.00x = 1,528,031.53
  5. Step 5: Solve for x
    x = 1,528,031.53/1,415.00
  6. Step 6: Final answer
    x = 1,079.88

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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.