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Finding the Fourth Proportional to 988.21, 1,482.32 and 257.79

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Solution

The fourth proportional to 988.21, 1,482.32 and 257.79 is: 386.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    988.21 : 1,482.32 = 257.79 : x
  2. Step 2: Convert to fraction form
    988.21/1,482.32 = 257.79/x
  3. Step 3: Cross multiply
    988.21x = 1,482.32 × 257.79
  4. Step 4: Simplify right side
    988.21x = 382,133.48
  5. Step 5: Solve for x
    x = 382,133.48/988.21
  6. Step 6: Final answer
    x = 386.69

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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.