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Finding the Fourth Proportional to 1,028.81, 1,418.02 and 780.05

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Solution

The fourth proportional to 1,028.81, 1,418.02 and 780.05 is: 1,075.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,028.81 : 1,418.02 = 780.05 : x
  2. Step 2: Convert to fraction form
    1,028.81/1,418.02 = 780.05/x
  3. Step 3: Cross multiply
    1,028.81x = 1,418.02 × 780.05
  4. Step 4: Simplify right side
    1,028.81x = 1,106,119.41
  5. Step 5: Solve for x
    x = 1,106,119.41/1,028.81
  6. Step 6: Final answer
    x = 1,075.15

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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.