Current location - Training Enrollment Network - Mathematics courses - Meaningful math problems in junior high school
Meaningful math problems in junior high school
Question 1. Downstream distance = upstream distance.

That is to say, the distance from A to B = the distance from B to A.

According to the meaning of the question,10 (3+u) = the distance from b to a.

The distance from b to a

Then 10 (3+u) < 12 (u-3)

30+ 10u< 12u-36

That is, u & gt33/h.

Question 2. Suppose you buy a breeding rabbit, then one year later, Lao Zhang has (a+2) rabbits and Lao Li has (2a- 1) rabbits.

Lao Zhang does not exceed 2/3 of the number of rabbits raised by Lao Li. Then (a+2)≤2/3(2a- 1).

Denominator 3(a+2)≤2(2a- 1)

That is 3a+6≤4a-2.

a≥8

When a=8 (a+2)=2/3(2a- 1), Lao Zhang is exactly 2/3 of Lao Li's rabbit breeding.

So Lao Zhang bought at least eight breeding rabbits a year ago.