100 5th grade math problems with answers Thirty points

Khan ...I'll help you with this.

x-(25-12)=64

Solution: x-13=64

x=64+13

x=77 solution: x=

x=the second! Right.

Solution: Suppose there are x bills of each type.

1x+2x+5x=160

8x=160

x=20 so a one-dimensional one has 1x=1 multiplied by 20, which is equal to 20.

The two-dimensional has 2x=2 multiplied by 20, which is equal to 40

5x of five = 5 times 20, equals 100.

x-(25-12)=64, then x=64+13, so x=77, then, x=, so x=

True/False: When n is a natural number (except 0), 2n-1 means an odd number (pair) If there are x notes for each of the three banknotes, then x+2x+5x=160

So 8x=160

Solution x=20

So 2x = 40 and 5x = 100

So there are 20 yuan for 1 yuan banknote, 40 yuan for 2 yuan banknote, and 100 yuan for 5 yuan banknote.

I didn't understand the first question, the second is right, and the third is to set the number of money to x, then x+2x+5x=160 8x= 160 x=20, so oh, but the first question really can't be seen.

(1)x-(25-12)=64

Solution: x-25+12=64

x-25=52

x=52+25

x=77 true/false:

When n is a natural number (except 0), 2n-1 means an odd number (correct) with the hypothesis method: when n is 1, 2n-1 = 1When n is 2, 2n-1=3

Xiaoling is a good child who is thrifty, she saved the pocket money given by her parents, including 1 yuan, 2 yuan, and 5 yuan banknotes, a total of 160 yuan, the number of three banknotes is the same, how many yuan are there for each of the three banknotes?

160 (1+2+5)=20 (sheets) 20*5=100 20*1=20 20*2=40

A: $5 is $100, $2 is $40, $1 is $20.

1. x-25+12=64 x-25=52 x=772. x=

3.Right. 4.If there are x pieces of 1 yuan banknote, then there are 2x pieces of 2 yuan banknotes, and there are 5x pieces of 5 yuan bills, and the system of equations: x + 2x + 5x = 160

8x=160 x=20, so there are 20 1 yuan notes, 40 2 yuan notes, and 100 5 yuan notes.

True or False:

When n is a natural number (except 0), 2n-1 means an odd number ( ) Xiaoling is a good child who saves, she saves the pocket money given by her parents, of which 1 yuan, 2 yuan, 5 yuan banknotes are a total of 160 yuan, the number of three banknotes is the same, how many yuan are there for each of the three banknotes?

Write ideas on the above inscriptions! The answer is 1

x-（25-12)=64

x-13=64

x=64+13

x=77x=When n is a natural number (except 0), 2n-1 represents an odd number for each = 160 (1+2+5)=20 x=

1 5 7 5 7 tons. This is the specific tonnage, and the total tonnage is divided by the number of portions, and the words "these fertilizers" and "full length" can be regarded as unit 1

What percentage of these fertilizers do each village get? That is to say, these fertilizers are whole, unit 1, that is, 1 is divided into 7 equal parts. So with 1 7 1 7

Note: The previous question is to ask the specific tonnage, and the unit should be brought. The latter question is to ask a few points, and you can't bring a unit.

2 17 + 23 + 9 = 49 people.

3 5-meter-long ropes are divided into 8 equal parts. The length of each serving is a fraction of the total length. The full length is the unit 1Divide into 8 portions equally. So 1 8 1 8

How many meters is each portion long?

There are unit meters after the question. So it's just asking for the specific length. With a concrete total length of 5 meters 8 5 8 meters. Remember to bring units.

4 Fold a 1-meter rope in half twice, which is a fraction of the total length of each piece of rope. Fold it and see that it's four paragraphs.

The same, the unit is 1 4 1 4

How many meters is each length of rope? Concrete 1 meter 4 1 4 meters.

This kind of question is mainly based on the problem. The question is followed by a unit, or the question is how many are how long they are, and the specific question is divided by the specific total.

If you ask how many fractions are, divide the unit one by the number of copies.

1. 5/7=

Tons of fertilizer per village? Each village receives one-seventh of this fertilizer.

Excellent 17 49 Good 23 49 Fair 9 493, 5 8=

The length of each portion is 5/8 of the total length, and the length of each portion is 5/8 of the meter.

This is 1/4 of the total length of each section of rope, and each section of rope is 1/4 of a meter long.

1.Each village was given 5 7 tons of fertilizer 1 7

2.Excellent 17 (17+23+9)=17 49 Good 23 49 Average 9 49

3 per serving is 1 8 each serving is 5 8 meters long.

4 Each section accounts for 1 4 The length of each section is 1 4 meters.

Question 1: The first question is 5 7 = 5 7 (tons) The second question: 1 7 = 1 7 Because the first question asks for the quantity, it is to divide 5 tons into 7 parts equally, and the second question asks for the number of parts, to regard 5 tons as a unit 1, and divide 1 into 7 parts equally.

Question 2: First find the total number of people 17 + 23 + 9 = 49 (people) 17 49 = 17 49 23 49 = 23 49 9 49 = 9 49

Three questions: 1 8 = 1 8 5 8 = 5 8 (m) The same question is the same.

Four questions: 1 4 = 1 4 1 4 = 1 4 (m).

5 divided by 7 = tons) equals five out of seven.

17 + 23 + 9 = 49 (person) 17 divided by 49 = seventeen forty-nine 23 divided by 49 = twenty-three forty-nine 9 divided by 49 = nine-nine-fourth.

5 divided by 8 = five eighths (meters).

1 divided by 2 = one-half of the length of each length of rope is one-half of a meter.

Generally 5 7 tons per village of 1 7 excellent 17 good 23 49 generally 9 49 per cent of the total length of each cent 5 8 per cent of the total length of 1 4 4 per section of the total length of 1 4 per section of 1 4 per section of the length of 1 4 meters per section of the total length of 1 4 meters per section of the total length of each section of the total length of 1 4 meters.

Each village receives five-sevenths of a tonne and each village receives one-seventh of the fertilizer.

Seventeen out of forty-nine are excellent, twenty-three out of nineteen are good, and nine out of forty-nine are average.

Each portion is one-eighth of the total length, and each portion is five-eighths of a meter long.

Each section of rope occupies a quarter of the total length, and each section of rope is a quarter of a meter long.

1.Divide the number directly by the total number, [5 7 tons] 1 number, [each village divides the total to 1 7].

2.Divide the number of students in each grade by the class size, 17 49 23 49 9 49

number, [1 8], 5 8 meters].

4.You can try it with a note [1 4] [1 4 meters].

1. 5/7。

2.Excellent: 17 class size; Good: 9 class size; General: 3 class sizes.

3.Each portion accounts for 5 8 of the total length; Each serving is 5 8 meters long.

4.(1 2 * 1 2 = 1 4) Each length of rope accounts for 1 4 ; Each section of rope is 1 4 meters long.

It is the study of fractions, it is recommended to study the example questions in the book, good luck.

8 is one-third of what the monk eats, and the remaining two-thirds! 8 2*3 is equal to 12, this is one-third of the eight precepts eaten, and two-thirds of it! 12 2*3 equals 18! There are 18 in total!

Bajie was greedy, first ate one-third, and there were two-thirds left, and Sha Seng ate the remaining one-third, that is, two-thirds of two-thirds, that is, two-thirds of the remaining two-thirds, four-nineths, that is, 8, 4 9x=8, x=18

Assuming that the distance from Xiao Ming's home to the school is x, 40 minutes = 2 3 hours, then x 9 + 2 3 = x 6

x/18=2/3

x=12, that is, the distance from Xiao Ming's home to the school is 12 kilometers.

Solution: 20 minutes = 1 3 hours, the distance from Xiao Ming's home to the school is x kilometers, then the normal time to the school is (x 9 + 1 3) hours; Or it can be expressed as (x 6-1 3) hours.

x/9+1/3=x/6-1/3

x/6-x/9=1/3+1/3

x/18=2/3

x=18×2/3

x=12A: The distance from Xiao Ming's house to the school is 12 kilometers.

[Analysis].

Traveling at a speed of 9 km) takes 40 minutes less than (traveling at a speed of 6 kmh), i.e. 2 3 hours.

Solution] Suppose the distance from Xiao Ming's home to the school is s

Then s 6 - s 9 = 2 3

S=12 can be obtained

The distance from Xiao Ming's home to the school is 12 kilometers.

v1=9km h, v2=6km h t2-t1=40 60 h distance is assumed to be s

Then s=v1*t1=v2*t2

Solve the equation 9t1 = 6t2

t2-t1=2/3

Launch t2 = 2 t1 = 4 3

Solution: Let the distance be x, then using the principle of time equality, there is the equation x 9 + 1 3 = x 6-1 3, and the solution equation is x = 12 (km).

That is, the distance between Xiao Ming's home and the school is 12 kilometers.

Let the distance be s kilometers, then there are s 6-s 9=40

S = 720 km.

If the original time from home to school is t hours, and the distance is x kilometers, then 9*(t-1 3)=x

6*(t+1/3)=x

Get t=3 5

x=12