Home / 291.89-437.79-86.42

Finding the Fourth Proportional to 291.89, 437.79 and 86.42

Calculator

Solution

The fourth proportional to 291.89, 437.79 and 86.42 is: 129.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    291.89 : 437.79 = 86.42 : x
  2. Step 2: Convert to fraction form
    291.89/437.79 = 86.42/x
  3. Step 3: Cross multiply
    291.89x = 437.79 × 86.42
  4. Step 4: Simplify right side
    291.89x = 37,833.81
  5. Step 5: Solve for x
    x = 37,833.81/291.89
  6. Step 6: Final answer
    x = 129.62

Related Problems

Find fourth proportional to 145.95, 218.90 and 43.21
Half scale
Find fourth proportional to 583.78, 875.58 and 172.84
Double scale
Find fourth proportional to 292.89, 439.29 and 87.42
Similar ratio
Find fourth proportional to 437.84, 656.69 and 129.63
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.