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Finding the Fourth Proportional to 688.80, 948.87 and 478.56

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Solution

The fourth proportional to 688.80, 948.87 and 478.56 is: 659.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.80 : 948.87 = 478.56 : x
  2. Step 2: Convert to fraction form
    688.80/948.87 = 478.56/x
  3. Step 3: Cross multiply
    688.80x = 948.87 × 478.56
  4. Step 4: Simplify right side
    688.80x = 454,091.23
  5. Step 5: Solve for x
    x = 454,091.23/688.80
  6. Step 6: Final answer
    x = 659.25

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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.