Finding the Fourth Proportional to 139.78, 209.71 and 58.63
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Solution
The fourth proportional to 139.78, 209.71 and 58.63 is: 87.96
Step by Step Solution
- Step 1: Write the proportion equation
139.78 : 209.71 = 58.63 : x - Step 2: Convert to fraction form
139.78/209.71 = 58.63/x - Step 3: Cross multiply
139.78x = 209.71 × 58.63 - Step 4: Simplify right side
139.78x = 12,295.24 - Step 5: Solve for x
x = 12,295.24/139.78 - Step 6: Final answer
x = 87.96
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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.