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Finding the Fourth Proportional to 290.54, 435.65 and 128.05

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Solution

The fourth proportional to 290.54, 435.65 and 128.05 is: 192.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.54 : 435.65 = 128.05 : x
  2. Step 2: Convert to fraction form
    290.54/435.65 = 128.05/x
  3. Step 3: Cross multiply
    290.54x = 435.65 × 128.05
  4. Step 4: Simplify right side
    290.54x = 55,783.25
  5. Step 5: Solve for x
    x = 55,783.25/290.54
  6. Step 6: Final answer
    x = 192.00

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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.