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Finding the Fourth Proportional to 878.08, 1,210.80 and 779.80

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Solution

The fourth proportional to 878.08, 1,210.80 and 779.80 is: 1,075.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    878.08 : 1,210.80 = 779.80 : x
  2. Step 2: Convert to fraction form
    878.08/1,210.80 = 779.80/x
  3. Step 3: Cross multiply
    878.08x = 1,210.80 × 779.80
  4. Step 4: Simplify right side
    878.08x = 944,181.84
  5. Step 5: Solve for x
    x = 944,181.84/878.08
  6. Step 6: Final answer
    x = 1,075.28

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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.