Finding the Fourth Proportional to 128,987.31, 177,992.73 and 72,387.75
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Solution
The fourth proportional to 128,987.31, 177,992.73 and 72,387.75 is: 99,889.62
Step by Step Solution
- Step 1: Write the proportion equation
128,987.31 : 177,992.73 = 72,387.75 : x - Step 2: Convert to fraction form
128,987.31/177,992.73 = 72,387.75/x - Step 3: Cross multiply
128,987.31x = 177,992.73 × 72,387.75 - Step 4: Simplify right side
128,987.31x = 12,884,493,241.06 - Step 5: Solve for x
x = 12,884,493,241.06/128,987.31 - Step 6: Final answer
x = 99,889.62
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1.5x scale
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.