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Finding the Fourth Proportional to 870.75, 1,200.96 and 649.35

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Solution

The fourth proportional to 870.75, 1,200.96 and 649.35 is: 895.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.75 : 1,200.96 = 649.35 : x
  2. Step 2: Convert to fraction form
    870.75/1,200.96 = 649.35/x
  3. Step 3: Cross multiply
    870.75x = 1,200.96 × 649.35
  4. Step 4: Simplify right side
    870.75x = 779,843.38
  5. Step 5: Solve for x
    x = 779,843.38/870.75
  6. Step 6: Final answer
    x = 895.60

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Double scale
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1.5x scale

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.