One ninth of a number is exactly the difference between four and two-thirds of three ② 2.5 times of a number minus 80% of 5 / 2, errand 2.5, find this number?

One ninth of a number is exactly the difference between four and two-thirds of three ② 2.5 times of a number minus 80% of 5 / 2, errand 2.5, find this number?

1,1/9x=4-3×2/3 x=18
2,2.5x-5/2×80%=2.5 x=9/5
9 out of 9
Xiao Fen spent 150 yuan on 15 gifts. It is known that each gift contains a packet of biscuits and two lollipops at 2 yuan each,
If the price of each packet of biscuits is x yuan, a linear equation with one yuan is given according to the meaning of the question
From the meaning of the title:
（x+2×2）×15=150
x+4=150÷15
x+4=10
X=6
A: each packet of biscuits costs 6 yuan
（x+2×2）×15=150
An is an equal ratio sequence, A4 + A7 = 2, a5a6 = - 8. A1 + A10 =?
Because it's an equal ratio sequence
So a4a7 = a5a6 = - 8
So A4 = 2, a7 = - 4 or A4 = - 2, a7 = 4
So A1 = - 1, A10 = 8. A1 + A10 = 7; or A1 = 1, A10 = - 8. A1 + A10 = - 7;
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A. The ratio of B and C is 7:9:12, and the difference between the sum of a and B minus C is 28
A is 7x, B is 9x, C is 12x
7x+9x-12x=28
4x=28
X=7
The three numbers are 49, 63 and 84
A kind of beverage, the original price was 2.4 yuan that day, now the store carries out promotion, the price of each bottle is 2 yuan, the original price of ten bottles of beverage, how many bottles can you buy at most now?
2.4X10=24
24/2=12
In the sequence of {an ·, A1}, and {an ·, A2} The minimum value of A4 + A5 is______ .
The ∵ sequence {an} is an equal ratio sequence, ∵ a4a5 = a1a8 = a2a7 = a3a6, ∵ A1 · A2 · So the answer is: 22
Three times the difference between a number and 1 / 3 is equal to 1 / 7 of 28. Find the number
3*(x-1/3)=28*(1/7)
x=5/3
This number is 5 / 3
3*(x-1/3)=28*(1/7)
x=5/3
This number is 5 / 3
5/3
It's two
The unit price of a drink is 1 yuan less than that of B drink. Xiaofeng bought 2 bottles of a drink and 3 bottles of B drink, which cost 13 yuan in total. If the unit price of B drink is x yuan / bottle, then the equation is as follows______ .
Suppose the unit price of B beverage is x yuan / bottle, then the unit price of a beverage is (x-1) yuan / bottle. From the meaning of the question: 2 (x-1) + 3x = 13, so the answer is: 2 (x-1) + 3x = 13
In {an}, A4 + A7 = 2, a5a6 = - 8, then a1 + a10=______ .
Therefore, A4 and A7 are two roots of the equation x2-2x-8 = 0, and the solution is A4 = 4, a7 = - 2; or A4 = - 2, a7 = 4. If A4 = 4, a7 = - 2, then Q3 = - 12, A1 = a4q3 = - 8, A10 = A7 · Q3 = 1, ｜ a1 + A10 = - 7
A number plus 4 equals 10 minus this number. What's this number
Equation. Complete
Let this number be X
x+4=10-x
x+x=10-4
2x=6
X=3