2- La longueur d'un rectangle mesure 2 cm de plus que le triple de sa largeur. Si le périmètre de ce rectangle est supérieur à 12 cm, mais d'au maximum 48 cm, dans quel intervalle se situe la largeur de ce rectangle?​

5 < L < 18,5

5 < L < 18,52 < W < 5,5

Step-by-step explanation:

longeur = length = L

largeur = width = W

L = 3W +2

12 < 2L+2W < 48

———————————————

12 < 2*(3W+2)+2W < 48

12 < 6W+4 +2W < 48

12 < 8W+4 < 48

8 < 8W < 44

2 < W < 5,5

———————————————

12 < 2L+2W < 48

L = 3W +2

L - 2 = 3W

L/3 -2/3 = W

12 < 2L +2*(L/3 -2/3) < 48

12 < 2L + ⅔L -4/3 < 48

12 < 2⅔L -4/3 < 48

13⅓ < 2⅔L < 49⅓

5 < L < 18,5

hope it helps.

exists in French too. .fr or switch country in app

The empirical rule states that approximately 68% of a normal distribution falls within one standard deviation of the mean, or . This means, by symmetry of the distribution, that

Now, since the distribution is symmetric about the mean, you have .

So,



More precisely, this probability is around .