Question

a sra. griffith relatou as pontuações de seus alunos no questionário mais recente.

pontuações do questionário
caule folha
3 | 4 6
4 | 0 4 6
5 | 1 1 2
6 | 0 3 9

quantos alunos marcaram pelo menos 57 pontos, mas menos de 65 pontos?

□ estudantes

Explanation:

Step1: Analyze stem (tens digit)

We need scores ≥57 and <65. So stem can be 5 (for 57 - 59) and 6 (for 60 - 64).

Step2: Analyze leaf for stem 5

Stem 5, leaf digits: 1,1,2. None ≥7 (since 57 needs leaf ≥7). So 0 students here.

Step3: Analyze leaf for stem 6

Stem 6, leaf digits: 0,3,9. We need <65, so leaf <5 (since 60 - 64: leaf 0,3 are <5; 9 is ≥5 so exclude). So leaf 0,3: 2 students.

Step4: Sum students

0 (stem 5) + 2 (stem 6) = 2? Wait, wait, correction: Wait, stem 5: scores are 51,51,52 (all <57). Stem 6: scores are 60,63,69. We need <65, so 60,63 (since 69 ≥65). Also, wait, did we miss stem 5? Wait, "pelo menos 57" means ≥57. So stem 5: leaves must be ≥7 (since 57: tens 5, units ≥7). But stem 5 leaves are 1,1,2 (all <7) → 0. Stem 6: tens 6, units <5 (since <65 → units 0 - 4). Stem 6 leaves: 0,3 (units 0,3 <5), 9 (units 9 ≥5 → exclude). So 2? Wait, no, wait: 60 is 60, which is ≥57 (yes, 60 ≥57) and <65 (yes, 60 <65). 63: 63 ≥57, <65. 69: 69 ≥65, so exclude. So stem 6 has 2 students (0 and 3). Wait, but also, is there stem 5 with leaves ≥7? No, stem 5 leaves are 1,1,2. So total is 2? Wait, maybe I made a mistake. Wait, the stem - and - leaf plot: "Caule" is stem, "Folha" is leaf. So for stem 3: leaves 4,6 → scores 34,36. Stem 4: leaves 0,4,6 → 40,44,46. Stem 5: leaves 1,1,2 → 51,51,52. Stem 6: leaves 0,3,9 → 60,63,69. Now, "pelo menos 57" (at least 57) and "menos de 65" (less than 65). So scores from 57 up to but not including 65. So 57,58,59,60,61,62,63,64. Now, check which scores are in the plot: - 57 - 59: are there any scores? The stem 5 scores are 51,51,52 (all <57) → no. - 60 - 64: scores 60,63 (since 60,63 are in the plot, 69 is 69 ≥65). So 60 and 63: that's 2 students? Wait, but wait, maybe I misread the stem - leaf. Wait, stem 5: leaves 1,1,2 → 51,51,52. Stem 6: leaves 0,3,9 → 60,63,69. So yes, 60 and 63 are between 57 (inclusive) and 65 (exclusive). So that's 2 students? Wait, but maybe the stem is the tens place, so 5|7 would be 57, but in the plot, stem 5 has leaves 1,1,2 (so 51,51,52), no 7,8,9. Stem 6 has leaves 0,3,9 (60,63,69). So 60 and 63: 2 students. Wait, but let's re - check the problem: "pelo menos 57" (≥57) and "menos de 65" (<65). So 57 ≤ score <65. So scores: 57,58,59,60,61,62,63,64. Now, from the stem - leaf: - 57 - 59: no scores (stem 5 has 51,51,52). - 60 - 64: 60 (6|0), 63 (6|3). 69 is 69 ≥65, so exclude. So that's 2 students. Wait, but maybe I made a mistake. Wait, is 60 ≥57? Yes, 60 ≥57. 63 ≥57? Yes. 60 <65? Yes. 63 <65? Yes. So two students. Wait, but let's count again. Stem 6 leaves: 0,3,9. So 60,63,69. We need <65, so 60 and 63: 2. Stem 5: no leaves ≥7. So total 2.

Answer:

2