The mathematics interest group held a test. There were 15 questions in the whole paper. It was stipulated that 8 points would be deducted for each right question and 4 points would be deducted for each wrong question. Xiaoying got 72 points in total, and she did it right______ Question

The mathematics interest group held a test. There were 15 questions in the whole paper. It was stipulated that 8 points would be deducted for each right question and 4 points would be deducted for each wrong question. Xiaoying got 72 points in total, and she did it right______ Question

The wrong questions are: (8 × 15-72) △ 8 + 4, = (120-72) △ 12, = 48 △ 12, = 4 (DAO); he did right: 15-4 = 11 (DAO); a: he did right 11 questions. So the answer is: 11

The mathematics interest group held a test. There were 15 questions in the whole paper. It was stipulated that 8 points would be deducted for each right question and 4 points would be deducted for each wrong question. Xiaoying got 72 points in total, and she did it right______ Question

The wrong questions are: (8 × 15-72) △ 8 + 4, = (120-72) △ 12, = 48 △ 12, = 4 (DAO); he did right: 15-4 = 11 (DAO); a: he did right 11 questions. So the answer is: 11

The puzzle Park held a mathematics competition, with 15 questions in total. 8 points for each right question, 4 points for each wrong question, 72 points in total. How many questions did you do right?

Full Score: 15 × 8 = 120 (points)
Deducted points: 120-72 = 48 (points)
Wrong answer: 8 + 4 = 12 (points)
48 △ 12 = 4 (question)
15-4 = 11
A: Xiao Kai did 11 questions right

The following group of incorrect interweaving of exponential and logarithmic expressions is ()
A. E0 = 1 and ln1 = 0b. 8 − 13 = 12 and log812 = − 13C. Log39 = 2 and 912 = 3D. Log77 = 1 and 71 = 7

E0 = 1 ⇔ ln1 = 0, so a is correct; 8 − 13 = 12 ⇔ log812 = − 13, so B is correct; log39 = 2 {32 = 9912 = 3} log93 = 12, so C is incorrect; log77 = 1 ⇔ 71 = 7, so D is correct

What is the value of expression 4 + 5 / 6 * 7 / 8 mod 9?
My algorithm is:
First, 6 * 7 = 42
Then 42 / 8 = 5.25
5\5.25=0
0Mod9=9
4+9=13
What's wrong?

0 mod 9 = 0. Mod is the remainder

Which three gorges does the Three Gorges refer to?

Qutang gorge, Wuxia gorge and Xiling Gorge

When x → 0, what order of infinitesimal is the function e ^ (SiNx) - e ^ x?
Such as the title

e^(sinx)－e^x＝e^x×[e^(sinx-x)－1].
When x → 0, e ^ x → 1, e ^ (sinx-x) - 1 is equivalent to sinx-x
Using Taylor formula, sinx-x = (x-x ^ 3 / 3! + 0 (x ^ 3)) - x = - 1 / 6 × x ^ 3 + 0 (x ^ 3)
Therefore, when x → 0, e ^ (SiNx) - e ^ x is of the same order as x ^ 3, so when x → 0, e ^ (SiNx) - e ^ x is infinitesimal of order 3 of X

There are 42 students in class 5 (1) of Wenhua Road Primary School, five of whom are Sanhao students?
emergency

5÷42=5/42
The number of Sanhao students accounts for 5 / 42 of the class

The nine numbers 26.27.28.29.30.31.32.33.34 add up to 90?

27 34 29
32 30 28
31 26 33

In the arithmetic sequence with 2n + 1 terms, if the sum of all odd terms is 165 and the sum of all even terms is 150, then n is equal to ()
A. 9B. 10C. 11D. 12

From the odd number term and S1 = (n + 1) (a1 + A2N + 1) 2 = (n + 1) × 2An + 12 = (n + 1) an + 1 = 165, ① even number term and S2 = n (A2 + A2N) 2 = n × 2An + 12 = Nan + 1 = 150, ② n + 1n = 165150, the solution is n = 10