There are 170 tons of grain in warehouse A and 90 tons of grain in warehouse B. after a part of grain is transferred from warehouse A to warehouse B, the tonnage of warehouse B is three fifths of warehouse A. how many tons of grain has been transferred from warehouse A to warehouse B

There are 170 tons of grain in warehouse A and 90 tons of grain in warehouse B. after a part of grain is transferred from warehouse A to warehouse B, the tonnage of warehouse B is three fifths of warehouse A. how many tons of grain has been transferred from warehouse A to warehouse B

Set warehouse A to warehouse B x tons
3/5(170-x)=90 x
The solution is x = 7.5 tons
A: 7.5 tons from warehouse A to warehouse B

To build a road, team a will build it in 6 days, while team B can build it 36 meters a day. Now the two teams work together. When the road is finished, the ratio of the length of the road built by team a and team B is 5:3

When it was finished, the whole length of the nail was repaired
5/(5+3)=5/8
One sixth of the total length of a is repaired every day
Total time: 5 / 8 △ 1 / 6 = 15 / 4 days
B: 1 / 15 / 4-1 / 6 = 1 / 10
Total length: 36 △ 1 / 10 = 360m

Simple calculation: 85.5 * 2345-85.4 * 1345

85.5*2345-85.4*1345
=85.4*2345-85.4*1345+0.1 *2345
=85.4*(2345-1345)+0.1 *2345
=85.4*1000+234.5
=85400+234.5
=85634.5

Finding limit: find the left and right limit of F (x) = x / X when x → 0, and explain whether the limit exists when x → 0
You can't take 0 as the denominator

Both the left and right limits are 1 (because x ≠ 0 at this time, it is infinite and tends to 0, so it can be reduced)
So x - > 0 limit exists
It's not said that the denominator is zero, X - > 0 (x tends to 0, which means not zero, but infinitely close),
This condition is also the range of X when you calculate limf (x), that is, when X - > 0, you calculate f (x)

X-15% x = 1.7

0.85x=1.7
x=2

-What do you want to fill in?
2 -3 5 ( ) 61 122
How much should I fill in?

It's fun. Best wishes!
twenty-eight
It's fun. Best wishes!

The limit of an is a, and the limit of BN is B +anbn)/n=ab 1,2,…… N is the subscript of a, B,

Stolz is obvious
If you don't know
If an tends to zero, then (a1 +. + an) / N also tends to zero
First of all, an must be bounded
That is, there is m > 0, for all N, there is | an | 0, there is n, when n > n | an | 0 < E
So there is
| A1 + ...+ An |

Function f (x) = lnsinx, find the definite integral value of X in the interval (0, Π / 2] f (x)

Note that the integral value is I, I = integral (0 to pi / 2) (LN2 + lnsinx / 2 + lncosx / 2) DX = (the third term is transformed, x = pi-t) pi / 2ln2 + integral (0 to pi / 2) lnsinx / 2DX + integral (PI / 2 to PI) lnsinx / 2DX = pi / 2ln2 + integral (0 to PI) lnsinx / 2DX = (x / 2 = t) pi / 2ln2 + 2I, I = - pi / 4

Primary school mathematics to find rules to fill in 2,3,5,7, (), 13,17, please help, very urgent. Thank you!

11

Known inequality 1n + 1 + 1n + 2 + +If 12n > a holds for all natural numbers n greater than 1, then the value range of a is ()
A. (−∞，13]B. (−∞，12]C. (−∞，712)D. （-∞，0]

Let f (n) = 1n + 1 + +12n, then f (n + 1) = 1n + 2 + +12n + 12n + 1 + 12 (n + 1), then f (n + 1) − f (n) = 12n + 1 + 12 (n + 1) − 1n + 1 = 12n + 1 − 12 (n + 1) = 12n + 1 − 12n + 2 ＞ 0, so the sequence f (n) is an increasing sequence of n (n ∈ n, n ≥ 2), so f (n) ≥ f (2) = 12 + 1 + 12 + 2 = 13 + 14 = 712, so the inequality 1n + 1 + 1n + 2 + +12n ＞ a holds for all natural numbers n greater than 1, so a ＜ 712