Finding the Fourth Proportional to 78.62, 108.51 and 54.09
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Solution
The fourth proportional to 78.62, 108.51 and 54.09 is: 74.65
Step by Step Solution
- Step 1: Write the proportion equation
78.62 : 108.51 = 54.09 : x - Step 2: Convert to fraction form
78.62/108.51 = 54.09/x - Step 3: Cross multiply
78.62x = 108.51 × 54.09 - Step 4: Simplify right side
78.62x = 5,869.31 - Step 5: Solve for x
x = 5,869.31/78.62 - Step 6: Final answer
x = 74.65
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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.