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Finding the Fourth Proportional to 1,980.39, 2,969.59 and 663.69

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Solution

The fourth proportional to 1,980.39, 2,969.59 and 663.69 is: 995.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,980.39 : 2,969.59 = 663.69 : x
  2. Step 2: Convert to fraction form
    1,980.39/2,969.59 = 663.69/x
  3. Step 3: Cross multiply
    1,980.39x = 2,969.59 × 663.69
  4. Step 4: Simplify right side
    1,980.39x = 1,970,887.19
  5. Step 5: Solve for x
    x = 1,970,887.19/1,980.39
  6. Step 6: Final answer
    x = 995.20

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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.