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Finding the Fourth Proportional to 281.51, 388.40 and 157.15

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Solution

The fourth proportional to 281.51, 388.40 and 157.15 is: 216.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.51 : 388.40 = 157.15 : x
  2. Step 2: Convert to fraction form
    281.51/388.40 = 157.15/x
  3. Step 3: Cross multiply
    281.51x = 388.40 × 157.15
  4. Step 4: Simplify right side
    281.51x = 61,036.76
  5. Step 5: Solve for x
    x = 61,036.76/281.51
  6. Step 6: Final answer
    x = 216.82

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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.