A stationer bought 2,000 exercise books. He distributed 200 exercise books to the students from poor economical background as donation. He sold each of the
remaining exercise books at Rs 10 more than the cost price of each and gained
8%, find the cost price of each exercise book.

answer:

The cost price is 125.

Step-by-step explanation:

Assuming the cost price is x.

x+1--x =8%

1

->x=125

The cost price is 125.

i have no answer for this maybe o 7 units

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)