Finding the Fourth Proportional to 172, 258 and 86.50
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Solution
The fourth proportional to 172, 258 and 86.50 is: 129.75
Step by Step Solution
- Step 1: Write the proportion equation
172 : 258 = 86.50 : x - Step 2: Convert to fraction form
172/258 = 86.50/x - Step 3: Cross multiply
172x = 258 × 86.50 - Step 4: Simplify right side
172x = 22,317 - Step 5: Solve for x
x = 22,317/172 - Step 6: Final answer
x = 129.75
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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.