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Finding the Fourth Proportional to 779.65, 1,075.47 and 499.32

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Solution

The fourth proportional to 779.65, 1,075.47 and 499.32 is: 688.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.65 : 1,075.47 = 499.32 : x
  2. Step 2: Convert to fraction form
    779.65/1,075.47 = 499.32/x
  3. Step 3: Cross multiply
    779.65x = 1,075.47 × 499.32
  4. Step 4: Simplify right side
    779.65x = 537,003.68
  5. Step 5: Solve for x
    x = 537,003.68/779.65
  6. Step 6: Final answer
    x = 688.78

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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.