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Finding the Fourth Proportional to 779.20, 1,075.65 and 499.54

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Solution

The fourth proportional to 779.20, 1,075.65 and 499.54 is: 689.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.20 : 1,075.65 = 499.54 : x
  2. Step 2: Convert to fraction form
    779.20/1,075.65 = 499.54/x
  3. Step 3: Cross multiply
    779.20x = 1,075.65 × 499.54
  4. Step 4: Simplify right side
    779.20x = 537,330.20
  5. Step 5: Solve for x
    x = 537,330.20/779.20
  6. Step 6: Final answer
    x = 689.59

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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.