Verified answer

Answer:

1. 5 years

2. 10%

Step-by-step explanation:

1. Given:

• I = 800
• P = 4,000
• R = 4% or 0.04
• T = ?

Use Interest formula

• I = PRT
• 800 = 4,000 × 0.04 × T
• 800 = 160T
• 800/160 = T
• 5 = T

Therefore , it will took 5 years

2. Given:

• P = 5,000
• F = 6,000
• T = 2 years
• R = ?

Use the Maturity value of simple interest

• F = P + (PRT)
• 6,000 = 5,000 + (5,000 × R × 2)
• 6,000 = 5,000 + 10,000R
• 6,000 - 5,000 = 10,000R
• 1,000 = 10,000R
• 1,000/10,000 = R
• 0.1 = R

or 0.1 × 100 = 10%

Therefore , the rate is 10%