Finding the Fourth Proportional to 78.76, 108.71 and 57.09
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Solution
The fourth proportional to 78.76, 108.71 and 57.09 is: 78.80
Step by Step Solution
- Step 1: Write the proportion equation
78.76 : 108.71 = 57.09 : x - Step 2: Convert to fraction form
78.76/108.71 = 57.09/x - Step 3: Cross multiply
78.76x = 108.71 × 57.09 - Step 4: Simplify right side
78.76x = 6,206.25 - Step 5: Solve for x
x = 6,206.25/78.76 - Step 6: Final answer
x = 78.80
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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.