Home / 1,376.80-2,055.08-1,290.40

Finding the Fourth Proportional to 1,376.80, 2,055.08 and 1,290.40

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Solution

The fourth proportional to 1,376.80, 2,055.08 and 1,290.40 is: 1,926.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,376.80 : 2,055.08 = 1,290.40 : x
  2. Step 2: Convert to fraction form
    1,376.80/2,055.08 = 1,290.40/x
  3. Step 3: Cross multiply
    1,376.80x = 2,055.08 × 1,290.40
  4. Step 4: Simplify right side
    1,376.80x = 2,651,875.23
  5. Step 5: Solve for x
    x = 2,651,875.23/1,376.80
  6. Step 6: Final answer
    x = 1,926.12

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.