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Finding the Fourth Proportional to 687.54, 948.84 and 678.36

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Solution

The fourth proportional to 687.54, 948.84 and 678.36 is: 936.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.54 : 948.84 = 678.36 : x
  2. Step 2: Convert to fraction form
    687.54/948.84 = 678.36/x
  3. Step 3: Cross multiply
    687.54x = 948.84 × 678.36
  4. Step 4: Simplify right side
    687.54x = 643,655.10
  5. Step 5: Solve for x
    x = 643,655.10/687.54
  6. Step 6: Final answer
    x = 936.17

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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.