The little boy said, "Auntie, I'll buy a box of biscuits and a bag of milk." then she handed me 10 yuan. Auntie said, "little friend, I bought a box of biscuits Biscuits are enough, but it's not enough to buy another bag of milk. Today is January 1, 2007. I'll give you a 10% discount on the biscuits I bought. Please take care of the two things and your change of 80 cents. "The little girl said," a box of biscuits is 7% more expensive than a bag of milk. " How much is a box of biscuits and a bag of milk? Also, it's better to use the equation to solve it Forget to say, with the equation of degree one variable

The little boy said, "Auntie, I'll buy a box of biscuits and a bag of milk." then she handed me 10 yuan. Auntie said, "little friend, I bought a box of biscuits Biscuits are enough, but it's not enough to buy another bag of milk. Today is January 1, 2007. I'll give you a 10% discount on the biscuits I bought. Please take care of the two things and your change of 80 cents. "The little girl said," a box of biscuits is 7% more expensive than a bag of milk. " How much is a box of biscuits and a bag of milk? Also, it's better to use the equation to solve it Forget to say, with the equation of degree one variable

Set milk as X, then biscuit (x + 7.9)
Get the equation
0.9（X+X+7.9）=9.2
X=1.045
So milk 1.045 yuan, biscuits 8.045 yuan

Auntie, I buy a box of biscuits and a bag of milk (10 yuan). A bag of biscuits is 7.9 yuan more expensive than a bag of milk! Children, you used to buy a box of biscuits with 10 yuan
It's enough, but it's not enough to buy another bag of milk! Today is children's day. I'll give you 10% discount on the biscuits I bought. Take two things, please! And find your eighty cents. Find out the price of a box of biscuits and a bag of milk. One yuan equation or inequality, not two yuan one time

If a box of biscuits costs X Yuan, then milk costs x-7.9 yuan
0.9x+x-7.9=10-0.8
1.9x=9.2+7.9
1.9x=17.1
x=9
Milk: x-7.9 = 9-7.9 = 1.1

Child: auntie, I'll buy a box of biscuits and a bag of milk. (give me 10 yuan) salesman: child, originally you used 10 yuan to buy a box of biscuits is enough
Yes, but it's not enough to buy another bag of milk. Today is January 1, 2010. I'll give you a 10% discount on the biscuits I bought. Please give me two things. I'll also give you 80 cents. A bag of milk is more expensive than a bag of biscuits. 7. How much is a box of biscuits and a bag of milk?

There is no way to do this problem. Just change it to "a bag of biscuits costs 7.9 yuan more than a bag of milk"
Let biscuit X Yuan, milk y yuan, y = x-7.9, 0.9x + y = 9.2
The solution is x = 9, y = 1.1
Biscuit 9 yuan, milk 1.1 yuan
9 + 1.1 > 10, so the answer is positive

Among all the five digit numbers, what are the numbers whose sum equals 43 and can be divided by 11?

9+9+9+9+7=43
9+9+9+8+8=43
So there are 97999997998989
3

Why can the rank of matrix equal to 1 be decomposed into the product of column vector and row vector
When can a matrix be decomposed into the product of column vector and row vector?

Let a be an n * n matrix, rank (a) = 1
Note a = (A1 ,an),ak,k=1,… And N is the n-dimensional column vector
Let a1 not be a zero vector, then rank (a) = 1
AK = BK * A1, BK is a number
So a = (A1, B2 * A1 ,bn*a1)=a1*(1,b2,… ,bn)
If a = UV, u is the column vector, V is the row vector, and u, V are not zero vectors, v = (V1 ,vn)
Then rank (a) = rank (UV) = rank (U (V1 ,vn))
=rank(uv1,… ,uvn)=1

5 / 6 of equation 1.18 is less than x 29 2. 4 / 5 of a certain number is more than 20% 24, find this number 3. 72 less than 60% of a certain number
5 / 6 of equation 1.18 is 29 less than x
2. 4 / 5 of a certain number is 24 more than 20%
3. The number 72 less than 60% of a certain number is 168
1. Use 120 cm long wire to form a rectangle. To make it 38 cm long, how many cm wide should it be? (equation)
2. A barrel of oil weighs 50kg. After 2 / 3 of the oil is poured out, the weight of the remaining oil is four times that of the barrel. How much is the net weight of the barrel? (equation)

1.18 * 5 / 6 = X-29, x = 44.2. Y * 4 / 5 = 0.2 + 24, y = 30.25.3. Z * 0.6-72 = 168, z = 400. (1) let the width x of the rectangle be: 2 * 38 + 2x = 120, x = 22 (CM). Let the net weight of the barrel be XKG, 1 / 3 * x = 4 * (50-x), 1 / 3 * x = 200-4x, x = 46.15 (kg)

If M and N are opposite to each other, find the value of M + n power - (π - 3.14) of 2012 to the power of 0

m. N is opposite to each other
∴m+n=0
The M + n power of 2012 and the 0 power of (π - 3.14)
=2012 to the power of 0-1
=1-1
=0

Wang Kai read a 200 page story book. On the first day, he read seven twentieth of the whole book. On the second day, he read one fifth of the whole book. On the third day, what page should he read

200 * 7 / 20 = 70 (page)
200 * 1 / 5 = 40 (page)
70 + 40 + 1 = 111 (page)
A: it should be read from page 111

Given that a and B are opposite numbers, m and N are reciprocal numbers, the absolute value of X is 2, find X & # 178; + 2a-3mn + 2B
the sooner the better

x²+2a-3mn+2b=2^2+2(a+b)-3*1=4+0-3=1

It takes 10 hours for a bus to go from a to B, and 15 hours for a freight train. The two trains run opposite each other at the same time. When they meet, the bus runs 96 kilometers more than the freight train
What is the distance between a and B?

The bus runs x km when meeting
X ：（X+96） = 1/15 ：1/10
1//10X = 1/15X + 6.4
1/30X=6.4
X = 192 km
Distance between the two places:
192 + 192 + 96 = 480km
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