Finding the Fourth Proportional to 1,280.81, 1,921.52 and 415.13
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Solution
The fourth proportional to 1,280.81, 1,921.52 and 415.13 is: 622.79
Step by Step Solution
- Step 1: Write the proportion equation
1,280.81 : 1,921.52 = 415.13 : x - Step 2: Convert to fraction form
1,280.81/1,921.52 = 415.13/x - Step 3: Cross multiply
1,280.81x = 1,921.52 × 415.13 - Step 4: Simplify right side
1,280.81x = 797,672.03 - Step 5: Solve for x
x = 797,672.03/1,280.81 - Step 6: Final answer
x = 622.79
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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.