Home / 1,315.28-1,974-666.20

Finding the Fourth Proportional to 1,315.28, 1,974 and 666.20

Calculator

Solution

The fourth proportional to 1,315.28, 1,974 and 666.20 is: 999.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,315.28 : 1,974 = 666.20 : x
  2. Step 2: Convert to fraction form
    1,315.28/1,974 = 666.20/x
  3. Step 3: Cross multiply
    1,315.28x = 1,974 × 666.20
  4. Step 4: Simplify right side
    1,315.28x = 1,315,078.80
  5. Step 5: Solve for x
    x = 1,315,078.80/1,315.28
  6. Step 6: Final answer
    x = 999.85

Related Problems

Find fourth proportional to 657.64, 987 and 333.10
Half scale
Find fourth proportional to 2,630.56, 3,948 and 1,332.40
Double scale
Find fourth proportional to 1,316.28, 1,975.50 and 667.20
Similar ratio
Find fourth proportional to 1,972.92, 2,961 and 999.30
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.