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Finding the Fourth Proportional to 777.30, 1,074.21 and 637.20

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Solution

The fourth proportional to 777.30, 1,074.21 and 637.20 is: 880.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    777.30 : 1,074.21 = 637.20 : x
  2. Step 2: Convert to fraction form
    777.30/1,074.21 = 637.20/x
  3. Step 3: Cross multiply
    777.30x = 1,074.21 × 637.20
  4. Step 4: Simplify right side
    777.30x = 684,487.81
  5. Step 5: Solve for x
    x = 684,487.81/777.30
  6. Step 6: Final answer
    x = 880.60

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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.