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Finding the Fourth Proportional to 1,239.79, 1,710.84 and 680.14

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Solution

The fourth proportional to 1,239.79, 1,710.84 and 680.14 is: 938.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,239.79 : 1,710.84 = 680.14 : x
  2. Step 2: Convert to fraction form
    1,239.79/1,710.84 = 680.14/x
  3. Step 3: Cross multiply
    1,239.79x = 1,710.84 × 680.14
  4. Step 4: Simplify right side
    1,239.79x = 1,163,610.72
  5. Step 5: Solve for x
    x = 1,163,610.72/1,239.79
  6. Step 6: Final answer
    x = 938.55

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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.