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Finding the Fourth Proportional to 780.05, 1,075.79 and 675.11

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Solution

The fourth proportional to 780.05, 1,075.79 and 675.11 is: 931.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.05 : 1,075.79 = 675.11 : x
  2. Step 2: Convert to fraction form
    780.05/1,075.79 = 675.11/x
  3. Step 3: Cross multiply
    780.05x = 1,075.79 × 675.11
  4. Step 4: Simplify right side
    780.05x = 726,271.21
  5. Step 5: Solve for x
    x = 726,271.21/780.05
  6. Step 6: Final answer
    x = 931.06

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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.