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Finding the Fourth Proportional to 1,308, 1,805.05 and 718.58

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Solution

The fourth proportional to 1,308, 1,805.05 and 718.58 is: 991.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,308 : 1,805.05 = 718.58 : x
  2. Step 2: Convert to fraction form
    1,308/1,805.05 = 718.58/x
  3. Step 3: Cross multiply
    1,308x = 1,805.05 × 718.58
  4. Step 4: Simplify right side
    1,308x = 1,297,060.21
  5. Step 5: Solve for x
    x = 1,297,060.21/1,308
  6. Step 6: Final answer
    x = 991.64

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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.