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Finding the Fourth Proportional to 687.81, 948.27 and 678.63

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Solution

The fourth proportional to 687.81, 948.27 and 678.63 is: 935.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.81 : 948.27 = 678.63 : x
  2. Step 2: Convert to fraction form
    687.81/948.27 = 678.63/x
  3. Step 3: Cross multiply
    687.81x = 948.27 × 678.63
  4. Step 4: Simplify right side
    687.81x = 643,524.47
  5. Step 5: Solve for x
    x = 643,524.47/687.81
  6. Step 6: Final answer
    x = 935.61

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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.