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Finding the Fourth Proportional to 780.36, 1,164.42 and 698.64

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Solution

The fourth proportional to 780.36, 1,164.42 and 698.64 is: 1,042.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.36 : 1,164.42 = 698.64 : x
  2. Step 2: Convert to fraction form
    780.36/1,164.42 = 698.64/x
  3. Step 3: Cross multiply
    780.36x = 1,164.42 × 698.64
  4. Step 4: Simplify right side
    780.36x = 813,510.39
  5. Step 5: Solve for x
    x = 813,510.39/780.36
  6. Step 6: Final answer
    x = 1,042.48

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.