Exercice 5 : (2 points) Je pense à un nombre, je lui ajoute 20, puis je double le résultat.
Curieusement je trouve 10 fois le nombre de départ ! Quel est le nombre pensé au départ ?

ow sorry i can't understand:( btw thank you for using))

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)

answer: 10 turtles

step-by-step explanation: as turtles have four legs so 4.10=40 therefore birds are 4 which sue counted