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Finding the Fourth Proportional to 785.88, 1,084.68 and 638.16

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Solution

The fourth proportional to 785.88, 1,084.68 and 638.16 is: 880.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    785.88 : 1,084.68 = 638.16 : x
  2. Step 2: Convert to fraction form
    785.88/1,084.68 = 638.16/x
  3. Step 3: Cross multiply
    785.88x = 1,084.68 × 638.16
  4. Step 4: Simplify right side
    785.88x = 692,199.39
  5. Step 5: Solve for x
    x = 692,199.39/785.88
  6. Step 6: Final answer
    x = 880.80

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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.