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Finding the Fourth Proportional to 687.07, 948.41 and 438.40

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Solution

The fourth proportional to 687.07, 948.41 and 438.40 is: 605.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.07 : 948.41 = 438.40 : x
  2. Step 2: Convert to fraction form
    687.07/948.41 = 438.40/x
  3. Step 3: Cross multiply
    687.07x = 948.41 × 438.40
  4. Step 4: Simplify right side
    687.07x = 415,782.94
  5. Step 5: Solve for x
    x = 415,782.94/687.07
  6. Step 6: Final answer
    x = 605.15

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1.5x scale

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.