Answers to unit 3 test paper 2009 of grade 5 Chinese volume 1

Answers to unit 3 test paper 2009 of grade 5 Chinese volume 1

I know the title: Grade 5 Volume 1 unit 3 test paper: Unit 3 standard and development training (time: 90 minutes, Full Score: 100 points) 1. Word basket. (25 points) 1. Round words. (10 points) m ǜ Qi á N J ī ng y à n t è zh ē ng J í C ù B ó w ù Gu ǎ n () () () () J

How to do the seventh question of the third lesson in the first volume of the fifth grade Chinese talent course
Reading is talking to a noble man
Reading,
Reading,

Reading is talking to a noble man
Reading is a guide to knowledge
Reading is for the rise of China

The tour company provides 4 tour routes for 3 tour groups, and each tour group chooses one of them
① Find out the probability of three tour groups choosing three different routes. ② find out the probability of two routes not being selected. ③ find out the expectation of the number of tour groups choosing route a

Solution: if "three tour groups choose three different routes" is event a, then p (a) = A34 / (4 ^ 3) = 3 / 8; if "just two routes are not selected" is event B, then p (b) = C24 × 2 ^ 3 / (4 ^ 3) = 3 / 4; if number of tour groups of route a = XX = 0,1,2,3p (x = 0) = 3 ^ 3 / (4 ^ 3) = 27 / 64p (x = 1) = C13 × 3 × 3 / (4 ^ 3) = 2

The equation x & # 178; + (M-3) x + M = 0 has two real roots of the same sign, and the value range of M is obtained
Why is the discriminant greater than or equal to 0? Should two real numbers be greater than 0

Because the title does not specify whether two real roots are equal, if the title is two real roots with the same sign but not equal, use greater than 0

A mathematical problem (solving equations)
{x²+y²=5
{2x²-3Xy-2y²=0
Solving the system of equations about X and Y

When 2x & # 178; - 3xy-2y & # 178; = 0 (2x + y) (x-2y) = 02x = - y or x = 2y2x = - y, X & # 178; + Y & # 178; = 5x & # 178; + 4x & # 178; = 5x & # 178; = 1x = ± 1 y = ± 2x = 2Y, 4Y & # 178; + Y & # 178; = 1y & # 178; = 1y = ± 1 x = ± 2

In the equal ratio sequence {an}, A1 = a, the sum of the first n terms is SN. If {an + 1} is an equal difference sequence, Sn?
It needs to be explained in detail

A1 = a, equal ratio = D
B1 = a + 1, equal difference = k
a2=a*d
b2=a*d+1=a+1+k
a3=a*d*d
b3=a*d*d+1=a+1+2k
a*d*d=a+2k;
a*d=a+k
(a+k)^2=a^2+2ka+k^2=(a+2k)a
k=0,
d=1
sn=n*a

How many kilograms is one ton? How many cubic decimeters is one cubic meter? How many cubic centimeters is one cubic decimeter? How many square meters is one square kilometer?

One ton equals 1000 kg, one cubic meter equals 100000 cubic decimeters, one cubic decimeter equals 100000 cubic centimeters, and one square kilometer equals 100000 square meters

For 360 tons of chemical fertilizer, 6 train skins and 15 cars were loaded; for 440 tons of chemical fertilizer, 8 train skins and 10 cars were loaded
Using binary linear equations to solve

Set X tons for train leather and Y tons for each car
therefore
6x+15y=360
2x+5y=120①
8x+10y=440
4x+5y=220②
② - 1
2x=100
X = 50
100+5y=120
y=4
So train leather 50 tons, car 4 tons

How many cubic miles is one cubic kilometer?

1 km = 2 li
So 1 cubic kilometer = 2 & # 179; cubic mile = 8 cubic mile
However, this unit is not very commonly used

8 (x-3) - 5x = 27 solved by equation

8x-24-5x=27
8x-5x=27+24
3x=51
x=17