Given ∠ e = 15 degrees, ∠ Abe = 110 degrees, ∠ ade = 65 degrees, find out the degree of ∠ a, write out the process, and To be clear, For the degree of ∠ a, our teacher said that the answer is 20 degrees, but I didn't understand

Given ∠ e = 15 degrees, ∠ Abe = 110 degrees, ∠ ade = 65 degrees, find out the degree of ∠ a, write out the process, and To be clear, For the degree of ∠ a, our teacher said that the answer is 20 degrees, but I didn't understand

B is larger than D: 110-65 = 45 degrees
A is: 65-45 = 20 degrees
Sister, is this the sixth grade question? I'm also in sixth grade. I'm a little dizzy. Is it a little difficult?

There are 45 students in class 6 (2). How many of them are born to the same person? Why?

Put 45 in 12 months on average, 3 students can be put in each month, and the remaining 9 students can be put in any 9 months, that is, there are at least 4 students in the 9 months, and the other months meet the requirements of the topic, that is, at least 3 students were born in the same month

Simple calculation
3.75 - (3 of 4-3 + 15, 3 of 3 + 15, 3 of 3-3 of 3-3 of 3-15, and the 17 of 15, which is divided into 3-3 of 3-3 of 3 + 15 of 3-3 of 3-3 of 3-4-3 of 3-15, and it will be 35; 3535;35;#\\35\\\\35\ \\\\\\\\\\\\\\\\\\\\\\\\\\(1.3-5 / 6)

3.75-(3/4+17/15)
=3.75-0.75-17/15
=3-17/15
=28/15
5/6+(1.3-5/6)
=5/6-5/6+1.3
=1.3

Simple calculation
2.5*9.8                  1.25*25*3.2

2.5*9.8=2.5*（10-0.2）=2.5*10-2.5*0.2=25-0.05=24.95
1.25*25*3.2=（0.25*5）*25*（4*0.8）=（0.25*4)*(25*4)*0.8=1*100*0.8=80
Most of these problems can be composed of simple arrays. Just rearrange the calculation array