Finding the Fourth Proportional to 84.78, 126.97 and 68.64
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Solution
The fourth proportional to 84.78, 126.97 and 68.64 is: 102.80
Step by Step Solution
- Step 1: Write the proportion equation
84.78 : 126.97 = 68.64 : x - Step 2: Convert to fraction form
84.78/126.97 = 68.64/x - Step 3: Cross multiply
84.78x = 126.97 × 68.64 - Step 4: Simplify right side
84.78x = 8,715.22 - Step 5: Solve for x
x = 8,715.22/84.78 - Step 6: Final answer
x = 102.80
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.