Question

What is the reminder when $4^{100}$is divided by 7 ?

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

Answer:

D. 4

$4^1=4-\frac{4}{7}=0$ -> reminder = 4

$4^2=16-\frac{16}{7}=2-2\times7=14$->reminder =2

$4^3=64-\frac{64}{7}=9-9\times 7=63$ reminder=1

$4^4=256-\frac{256}{7}=36-36\times7=252$->reminder=4