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Finding the Fourth Proportional to 1,979.88, 2,970.80 and 992.80

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Solution

The fourth proportional to 1,979.88, 2,970.80 and 992.80 is: 1,489.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,979.88 : 2,970.80 = 992.80 : x
  2. Step 2: Convert to fraction form
    1,979.88/2,970.80 = 992.80/x
  3. Step 3: Cross multiply
    1,979.88x = 2,970.80 × 992.80
  4. Step 4: Simplify right side
    1,979.88x = 2,949,410.24
  5. Step 5: Solve for x
    x = 2,949,410.24/1,979.88
  6. Step 6: Final answer
    x = 1,489.69

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.