Finding the Fourth Proportional to 128,990.31, 177,996.86 and 72,390.75
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Solution
The fourth proportional to 128,990.31, 177,996.86 and 72,390.75 is: 99,893.75
Step by Step Solution
- Step 1: Write the proportion equation
128,990.31 : 177,996.86 = 72,390.75 : x - Step 2: Convert to fraction form
128,990.31/177,996.86 = 72,390.75/x - Step 3: Cross multiply
128,990.31x = 177,996.86 × 72,390.75 - Step 4: Simplify right side
128,990.31x = 12,885,326,193.05 - Step 5: Solve for x
x = 12,885,326,193.05/128,990.31 - Step 6: Final answer
x = 99,893.75
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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.