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Finding the Fourth Proportional to 765.07, 1,055.97 and 485.70

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Solution

The fourth proportional to 765.07, 1,055.97 and 485.70 is: 670.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    765.07 : 1,055.97 = 485.70 : x
  2. Step 2: Convert to fraction form
    765.07/1,055.97 = 485.70/x
  3. Step 3: Cross multiply
    765.07x = 1,055.97 × 485.70
  4. Step 4: Simplify right side
    765.07x = 512,884.63
  5. Step 5: Solve for x
    x = 512,884.63/765.07
  6. Step 6: Final answer
    x = 670.38

Related Problems

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Half scale
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Double scale
Find fourth proportional to 766.07, 1,057.35 and 486.70
Similar ratio
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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.