Home / 496.41-685.19-309.78

Finding the Fourth Proportional to 496.41, 685.19 and 309.78

Calculator

Solution

The fourth proportional to 496.41, 685.19 and 309.78 is: 427.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    496.41 : 685.19 = 309.78 : x
  2. Step 2: Convert to fraction form
    496.41/685.19 = 309.78/x
  3. Step 3: Cross multiply
    496.41x = 685.19 × 309.78
  4. Step 4: Simplify right side
    496.41x = 212,258.16
  5. Step 5: Solve for x
    x = 212,258.16/496.41
  6. Step 6: Final answer
    x = 427.59

Related Problems

Find fourth proportional to 248.21, 342.60 and 154.89
Half scale
Find fourth proportional to 992.82, 1,370.38 and 619.56
Double scale
Find fourth proportional to 497.41, 686.57 and 310.78
Similar ratio
Find fourth proportional to 744.62, 1,027.79 and 464.67
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.