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Finding the Fourth Proportional to 1,279.57, 1,765.74 and 720.07

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Solution

The fourth proportional to 1,279.57, 1,765.74 and 720.07 is: 993.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.57 : 1,765.74 = 720.07 : x
  2. Step 2: Convert to fraction form
    1,279.57/1,765.74 = 720.07/x
  3. Step 3: Cross multiply
    1,279.57x = 1,765.74 × 720.07
  4. Step 4: Simplify right side
    1,279.57x = 1,271,456.40
  5. Step 5: Solve for x
    x = 1,271,456.40/1,279.57
  6. Step 6: Final answer
    x = 993.66

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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.