Home / 1,387.04-2,080.85-646.10

Finding the Fourth Proportional to 1,387.04, 2,080.85 and 646.10

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Solution

The fourth proportional to 1,387.04, 2,080.85 and 646.10 is: 969.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.04 : 2,080.85 = 646.10 : x
  2. Step 2: Convert to fraction form
    1,387.04/2,080.85 = 646.10/x
  3. Step 3: Cross multiply
    1,387.04x = 2,080.85 × 646.10
  4. Step 4: Simplify right side
    1,387.04x = 1,344,423.55
  5. Step 5: Solve for x
    x = 1,344,423.55/1,387.04
  6. Step 6: Final answer
    x = 969.28

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.