Answer:
39
Step-by-step explanation:
20
+ 19
———>>> 0+9= 9
——-> 39
2+1= 3
Let the height of the trees are h1,h2 and h3,
Then,we know that
Mean height=(h1+h2+h3)/3
For 12a, they are asking about winter sports, they could ask about all sports.
For 12b, they ask an audience about the show they came to see; which is inherently a bias as they are going to be partial towards certain contestants; they could ask them about random contestants of unaffiliated shows.
For 13a, it should be continuous, and I'm sorry but I don't know the types of graphs available.
For 13b, I believe it should be discreet, and once again apologize for not knowing the types of graphs.
7/4 ÷ 8/7
To divide fraction multiply the first fraction by the reciprocal of the second fraction:
7/4 x 7/8 = (7x7) / (4x8) = 49/32
