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Finding the Fourth Proportional to 712.80, 982.80 and 492.36

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Solution

The fourth proportional to 712.80, 982.80 and 492.36 is: 678.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.80 : 982.80 = 492.36 : x
  2. Step 2: Convert to fraction form
    712.80/982.80 = 492.36/x
  3. Step 3: Cross multiply
    712.80x = 982.80 × 492.36
  4. Step 4: Simplify right side
    712.80x = 483,891.41
  5. Step 5: Solve for x
    x = 483,891.41/712.80
  6. Step 6: Final answer
    x = 678.86

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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.