4. The values of expression 4 mod 7 ^ 2 + 15 / 3 are (). A, 6 B, 7 C, 8 D, 9

4. The values of expression 4 mod 7 ^ 2 + 15 / 3 are (). A, 6 B, 7 C, 8 D, 9

The priority of mod and / is the same, and the priority of + is lower than that of mod and / or/
So first calculate 4 mod 7 ^ 2, then 15 / 2, and then the sum of the first two
4 MOD 49 = 4
15 / 3 = 5
4 + 5 = 9
So, choose D

The value of expression 10 * 8 Mod 5 * 2 / 8?
The teacher writes 0,0, calculates 7.5 by himself (Baidu science computer is also this)

0,
10*8=80
80mod5=0
0*2/8=0

Write the form of X, such as ax + B equals C (a is not equal to 0), so that its solution is - 3 and 10 / 3 respectively

7x-5 = - 26, the solution is - 3
6x-2 = 18, the solution is 10 / 3

The distance between a and B is 880 meters. The car starts from A. two hours later, the bus starts from B. the two cars meet again after four hours
It is known that the car travels 20 kilometers more per hour than the bus. Q: how many kilometers does the bus travel per hour

The bus travels x kilometers per hour, while the car travels (x + 20) kilometers per hour
880=(x+20)*2+(x+20+x)*4
Solution
x=76

I was asked down today. What a shame. Under the root sign (the square of a + 2008) is an integer. Find the value of the smallest positive integer a that meets the condition

Root 2008 = 44
a^2+2ax+x^2
2ax+x^2=2008
2a=（2008/x ） - x
So x must be even
X = 2
2a=1004-2=1002
a=501
When x = 4
2a=502-4=498
a=249
When x = 6
no way.
therefore
a=249

Factorization (x ^ 2-4x + 3) (x ^ 2 + 6x + 8) + 24

Original formula = (x-1) (x-3) (x + 2) (x + 4) + 24 = [(x-1) (x + 2)] [(x-3) (x + 4)] + 24 = [(X & # 178; + x) - 2] [(X & # 178; + x) - 12] + 24 = (X & # 178; + x) &# 178; - 14 (X & # 178; + x) + 48 = (X & # 178; + X-6) (X & # 178; + X-8) = (x + 3) (X-2) (X & # 178; + X-8)

Apple, banana and pear were transported to the fruit shop. The weight of apple and banana was 87kg, and that of pear and banana was 100kg
Then above: the weight of banana is 37.5% of the fruit. How many kilos of fruit are there?

Let apple be AKG, banana be bkg, pear be CKG and total weight be mkg
A+B=87
C+B=100
B/M=0.375
So, a + B + C + B = 100 + 87
That is, M + B = 187
B=187-M
187-M=0.375M
M=136
The total weight is 136

The solution set of inequality 1 less than | X-2 | less than or equal to 3 is

13 or X

What is the square of X equal to 64? What is the third power of X equal to 64?

The square of X is 64
X = ± root (64)
x=±8
The third power of X is 64,
X = root of degree 3 (64)
x=4

The fruit shop delivered a batch of watermelons, which sold 60 kg more than 3 / 5 of the total. The rest was 1 / 3 of the total. How many kg are these watermelons?

60 kg more than three fifths of the total,
The rest is 60 kg less than two fifths of the total,
We know that the rest is one third of the sales,
Then the rest is (3 / 5 of the total + 60) * 1 / 3 = 1 / 5 of the total + 20 kg
therefore
The total number of watermelons in this batch
=(60+20)/(2/5-1/5)
=80/(1/5)
=400kg