Home / 1,324-1,986.72-640

Finding the Fourth Proportional to 1,324, 1,986.72 and 640

Calculator

Solution

The fourth proportional to 1,324, 1,986.72 and 640 is: 960.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,324 : 1,986.72 = 640 : x
  2. Step 2: Convert to fraction form
    1,324/1,986.72 = 640/x
  3. Step 3: Cross multiply
    1,324x = 1,986.72 × 640
  4. Step 4: Simplify right side
    1,324x = 1,271,500.80
  5. Step 5: Solve for x
    x = 1,271,500.80/1,324
  6. Step 6: Final answer
    x = 960.35

Related Problems

Find fourth proportional to 662, 993.36 and 320
Half scale
Find fourth proportional to 2,648, 3,973.44 and 1,280
Double scale
Find fourth proportional to 1,325, 1,988.22 and 641
Similar ratio
Find fourth proportional to 1,986, 2,980.08 and 960
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.