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Finding the Fourth Proportional to 1,309.71, 1,807.47 and 720.30

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Solution

The fourth proportional to 1,309.71, 1,807.47 and 720.30 is: 994.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,309.71 : 1,807.47 = 720.30 : x
  2. Step 2: Convert to fraction form
    1,309.71/1,807.47 = 720.30/x
  3. Step 3: Cross multiply
    1,309.71x = 1,807.47 × 720.30
  4. Step 4: Simplify right side
    1,309.71x = 1,301,920.64
  5. Step 5: Solve for x
    x = 1,301,920.64/1,309.71
  6. Step 6: Final answer
    x = 994.05

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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.