Home / 135-186.30-76.78

Finding the Fourth Proportional to 135, 186.30 and 76.78

Calculator

Solution

The fourth proportional to 135, 186.30 and 76.78 is: 105.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    135 : 186.30 = 76.78 : x
  2. Step 2: Convert to fraction form
    135/186.30 = 76.78/x
  3. Step 3: Cross multiply
    135x = 186.30 × 76.78
  4. Step 4: Simplify right side
    135x = 14,304.35
  5. Step 5: Solve for x
    x = 14,304.35/135
  6. Step 6: Final answer
    x = 105.96

Related Problems

Find fourth proportional to 67.50, 93.15 and 38.39
Half scale
Find fourth proportional to 270, 372.60 and 153.56
Double scale
Find fourth proportional to 136, 187.68 and 77.78
Similar ratio
Find fourth proportional to 202.50, 279.45 and 115.17
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.