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Finding the Fourth Proportional to 779.60, 1,075.80 and 484.78

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Solution

The fourth proportional to 779.60, 1,075.80 and 484.78 is: 668.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.60 : 1,075.80 = 484.78 : x
  2. Step 2: Convert to fraction form
    779.60/1,075.80 = 484.78/x
  3. Step 3: Cross multiply
    779.60x = 1,075.80 × 484.78
  4. Step 4: Simplify right side
    779.60x = 521,526.32
  5. Step 5: Solve for x
    x = 521,526.32/779.60
  6. Step 6: Final answer
    x = 668.97

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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.