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Finding the Fourth Proportional to 989.60, 1,484.84 and 340.80

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Solution

The fourth proportional to 989.60, 1,484.84 and 340.80 is: 511.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    989.60 : 1,484.84 = 340.80 : x
  2. Step 2: Convert to fraction form
    989.60/1,484.84 = 340.80/x
  3. Step 3: Cross multiply
    989.60x = 1,484.84 × 340.80
  4. Step 4: Simplify right side
    989.60x = 506,033.47
  5. Step 5: Solve for x
    x = 506,033.47/989.60
  6. Step 6: Final answer
    x = 511.35

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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.