Finding the Fourth Proportional to 172.63, 258.73 and 86
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Solution
The fourth proportional to 172.63, 258.73 and 86 is: 128.89
Step by Step Solution
- Step 1: Write the proportion equation
172.63 : 258.73 = 86 : x - Step 2: Convert to fraction form
172.63/258.73 = 86/x - Step 3: Cross multiply
172.63x = 258.73 × 86 - Step 4: Simplify right side
172.63x = 22,250.78 - Step 5: Solve for x
x = 22,250.78/172.63 - Step 6: Final answer
x = 128.89
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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.