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Finding the Fourth Proportional to 879.80, 1,210.14 and 778.28

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Solution

The fourth proportional to 879.80, 1,210.14 and 778.28 is: 1,070.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    879.80 : 1,210.14 = 778.28 : x
  2. Step 2: Convert to fraction form
    879.80/1,210.14 = 778.28/x
  3. Step 3: Cross multiply
    879.80x = 1,210.14 × 778.28
  4. Step 4: Simplify right side
    879.80x = 941,821.71
  5. Step 5: Solve for x
    x = 941,821.71/879.80
  6. Step 6: Final answer
    x = 1,070.50

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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.