Finding the Fourth Proportional to 861.60, 1,187.76 and 828
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Solution
The fourth proportional to 861.60, 1,187.76 and 828 is: 1,141.44
Step by Step Solution
- Step 1: Write the proportion equation
861.60 : 1,187.76 = 828 : x - Step 2: Convert to fraction form
861.60/1,187.76 = 828/x - Step 3: Cross multiply
861.60x = 1,187.76 × 828 - Step 4: Simplify right side
861.60x = 983,465.28 - Step 5: Solve for x
x = 983,465.28/861.60 - Step 6: Final answer
x = 1,141.44
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.