Finding the Fourth Proportional to 128,988.31, 177,994.10 and 72,388.75
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Solution
The fourth proportional to 128,988.31, 177,994.10 and 72,388.75 is: 99,890.99
Step by Step Solution
- Step 1: Write the proportion equation
128,988.31 : 177,994.10 = 72,388.75 : x - Step 2: Convert to fraction form
128,988.31/177,994.10 = 72,388.75/x - Step 3: Cross multiply
128,988.31x = 177,994.10 × 72,388.75 - Step 4: Simplify right side
128,988.31x = 12,884,770,587.35 - Step 5: Solve for x
x = 12,884,770,587.35/128,988.31 - Step 6: Final answer
x = 99,890.99
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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.