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Finding the Fourth Proportional to 675.10, 1,005.55 and 643.50

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Solution

The fourth proportional to 675.10, 1,005.55 and 643.50 is: 958.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    675.10 : 1,005.55 = 643.50 : x
  2. Step 2: Convert to fraction form
    675.10/1,005.55 = 643.50/x
  3. Step 3: Cross multiply
    675.10x = 1,005.55 × 643.50
  4. Step 4: Simplify right side
    675.10x = 647,071.43
  5. Step 5: Solve for x
    x = 647,071.43/675.10
  6. Step 6: Final answer
    x = 958.48

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.