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Finding the Fourth Proportional to 1,220.40, 1,827.36 and 642.06

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Solution

The fourth proportional to 1,220.40, 1,827.36 and 642.06 is: 961.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.40 : 1,827.36 = 642.06 : x
  2. Step 2: Convert to fraction form
    1,220.40/1,827.36 = 642.06/x
  3. Step 3: Cross multiply
    1,220.40x = 1,827.36 × 642.06
  4. Step 4: Simplify right side
    1,220.40x = 1,173,274.76
  5. Step 5: Solve for x
    x = 1,173,274.76/1,220.40
  6. Step 6: Final answer
    x = 961.39

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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.