Home / 754.12-1,130.10-428.80

Finding the Fourth Proportional to 754.12, 1,130.10 and 428.80

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Solution

The fourth proportional to 754.12, 1,130.10 and 428.80 is: 642.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    754.12 : 1,130.10 = 428.80 : x
  2. Step 2: Convert to fraction form
    754.12/1,130.10 = 428.80/x
  3. Step 3: Cross multiply
    754.12x = 1,130.10 × 428.80
  4. Step 4: Simplify right side
    754.12x = 484,586.88
  5. Step 5: Solve for x
    x = 484,586.88/754.12
  6. Step 6: Final answer
    x = 642.59

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.