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Finding the Fourth Proportional to 1,978.68, 2,968.80 and 680.28

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Solution

The fourth proportional to 1,978.68, 2,968.80 and 680.28 is: 1,020.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,978.68 : 2,968.80 = 680.28 : x
  2. Step 2: Convert to fraction form
    1,978.68/2,968.80 = 680.28/x
  3. Step 3: Cross multiply
    1,978.68x = 2,968.80 × 680.28
  4. Step 4: Simplify right side
    1,978.68x = 2,019,615.26
  5. Step 5: Solve for x
    x = 2,019,615.26/1,978.68
  6. Step 6: Final answer
    x = 1,020.69

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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.