Finding the Fourth Proportional to 128,986.68, 177,991.86 and 72,387.12
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Solution
The fourth proportional to 128,986.68, 177,991.86 and 72,387.12 is: 99,888.75
Step by Step Solution
- Step 1: Write the proportion equation
128,986.68 : 177,991.86 = 72,387.12 : x - Step 2: Convert to fraction form
128,986.68/177,991.86 = 72,387.12/x - Step 3: Cross multiply
128,986.68x = 177,991.86 × 72,387.12 - Step 4: Simplify right side
128,986.68x = 12,884,318,128.84 - Step 5: Solve for x
x = 12,884,318,128.84/128,986.68 - Step 6: Final answer
x = 99,888.75
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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.