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There are four ninth out of four math problems in the fifth grade of primary school, so what are there seven in two seventh
two-forty-ninths
one-seventh
Four ninths out of four ninths, then seven halves out of two sevens
Little Man
2/49…… There are seven 49 / 2
2 / 7 of 7 = 2 / 49
Fill in 1, 2, 3, 4, 5, 6, 7, 8 and 9 in () to form three formulas. Each number can only be used once
First: (2) * (3) = (6)
（ 7）＋（ 1）＝（8 ）
（ 4）＋（5 ）＝（9 ）
The second: (6) / (2) = (3)
（5 ）＋（4 ）＝（9 ）
（7 ）＋（1）＝（8 ）
The third: (9) - (4) = (5)
（2 ）*（ 3）＝（6 ）
（ 8）-（1 ）＝（7 ）
and so on
For a story book, Xiao Hong read 3 / 8 of the whole book on the first day, 3 / 10 of the whole book on the second day, and finished it on the third day
How many parts of this book did you read on the third day?
1-3/8-3/10
=5/8-3/10
=25/40-12/40
=13/40
A: I read 13 out of 40 books
-1 / 2, 2 / 3, - 3 / 4, 4 / 5, - 5 / 6, 6 / 7 The ninth number is () and the 2001 number is ()
-9 out of 10 and - 2001 out of 2002
-9/10
-2001/2002
-9 / 10 and - 2001 / 2002
9 8 7 6 5 4 3 2 1 how to use addition, subtraction, multiplication and division to equal 22
9+8*7-6*5-4*3-2+1=22
[(9-8)-(7-6)]+5x4+3-2+1
9+8+7+6-5-4+3-2÷1=22
1*2+3-4+5+6-7+8+9
（9+8-7)*6/5+4+3*2*1
It took Xiao Hong three days to finish reading a story book. On the first day, she read 3 / 1 of the whole book, and on the second day, she read the remaining 5 / 2. It is known that she read 24 times less on the second day than on the third day
How many pages does the story book come to?
A total of 180 pages, the solution is, let this book have y pages, the third day I read x pages, then 1 / 3Y + 2 / 3Y * 2 / 5 + x = y, 2 / 3Y * 2 / 5 + 24 = X
Y = 180, x = 72
Let the whole book be X,,
One third x on the first day
The next day, 2 / 3 x multiplied by 2 / 5
On the third day, 2 / 3 x times 2 / 5 + 24
Format 3 / x + (3 / 2x * 5 / 2) + (3 / 2x * 5 / 2 + 24) = x conversion, multiply all by 15 to remove fractions
5X+4X+4X+360=15X
... unfold
Let the whole book be X,,
One third x on the first day
The next day, 2 / 3 x multiplied by 2 / 5
On the third day, 2 / 3 x times 2 / 5 + 24
Format 3 / x + (3 / 2x * 5 / 2) + (3 / 2x * 5 / 2 + 24) = x conversion, multiply all by 15 to remove fractions
5X+4X+4X+360=15X
2X = 360
X = 180 ° Stow
(cycle of 3.22 + cycle of 1.33 + cycle of 4.66 + cycle of 2.44) divided by one third, the process and result are calculated
(cycle of 3.2 2 + cycle of 1.3 3 + cycle of 4.6 6 + cycle of 2.4 4) divided by one third,
=(3 2 / 9 + 1 1 / 3 + 4 2 / 3 + 2 4 / 9) × 3
=11 2 / 3 × 3
=33+2
=35
That's all
(3.2 2 cycles + 1.3 3 cycles + 4.6 6 cycles + 2.4 4 cycles) divided by one third
=(3 + 2 / 9 + 1 + 1 / 3 + 4 + 2 / 3 + 2 + 4 / 9) △ 1 / 3
=11 and 2 / 3 △ 1 / 3
=35
22 cycle = 2 / 9, 0.33 cycle = 3 / 9, 0.44 cycle = 4 / 9; 0.66 cycle = 6 / 9,
2 / 9 + 3 / 9 + 6 / 9 + 4 / 9 + 3 + 1 + 4 + 2 = 10 + 15 / 9 original question = (10 + 15 / 9) X3 = 30 + 5 = 35
It's the sum of 1 and 2 / 9 plus 1 and 3 / 1 plus 4 and 3 / 2 plus 2 and 9 / 4, divided by 1 / 3, and finally it's 35
Six four's plus, minus, multiply and divide equal five and seven and eight and nine and ten
（4+4+4+4+4）÷4=5
（4×4+4+4+4）÷4=7
4×4+4-4-4-4=8
4+4+（4+4-4）÷4=9
（4×4+4+4）÷4+4=10
(4+4+4+4+4)/4=5
(4+4)-4/4-4/4=6
(4*4+4+4+4)/4=7
4+4+4+4-4-4=8
4/4+4+4+4-4=9
4/4+4/4+4+4=10
4+4-(4+4+4)/4=5
4*4/4+4-4/4=7
4*4*4/4/4+4=8
4*4/4+4+4/4=9
4+4+4/4+4/4=10
A story book read two fifths of the first day, read the remaining quarter the second day, and read what percentage of the whole book the next day?
I read two fifths of a story book on the first day, the remaining quarter on the second day, and what percentage of the whole book on the second day?
（1-2/5）×1/4
=3/5×1/4
=3/20
A new operation: a × B = 1 / A + 1 / B, then 1 × 2=
If a × B = 1 / A + 1 / B, then 1 × 2 = 1 / 1 + 1 / 2 = 3 / 2 = 1.5
1X2=1/1+1/2=3/2
It's 3 / 2.
=1+1/2=3/2
＝1/1 1/2＝3/2
1×2=1/1+1/2=3/2=1.5
1+1/2=3/2
∵a×b=1/a+1/b,
∴1×2=1/1+1/2=2/2+1/2=3/2=1.5.
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