Home / 687.03-1,028.58-426.25

Finding the Fourth Proportional to 687.03, 1,028.58 and 426.25

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Solution

The fourth proportional to 687.03, 1,028.58 and 426.25 is: 638.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.03 : 1,028.58 = 426.25 : x
  2. Step 2: Convert to fraction form
    687.03/1,028.58 = 426.25/x
  3. Step 3: Cross multiply
    687.03x = 1,028.58 × 426.25
  4. Step 4: Simplify right side
    687.03x = 438,432.23
  5. Step 5: Solve for x
    x = 438,432.23/687.03
  6. Step 6: Final answer
    x = 638.16

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1.5x scale

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.