There are 24 boys in class 6.2, 20% less than girls. How many girls are there in class 6.2? How many students are there in the whole class? Please explain the parallel formula

There are 24 boys in class 6.2, 20% less than girls. How many girls are there in class 6.2? How many students are there in the whole class? Please explain the parallel formula

24 (1-20%) = 30 (person)
24 + 30 = 54 (person)

5 is less than 80%, 35 is 70%, 24 is less than 48%, 50 is more than 20%, 110 is more than 11%,
30 is less than 60 percent, 6 is more than 4 percent, 20 is 40 percent, 5 is 50 percent, 7 is 10 percent, 12 is less than 60 percent

75/80*100%=93.75%
35/70*100%=50%
(48-24)/48*100%=50%
(50-20)/20*100%=150%
(110-11)/11*100%=900%
(60-30)/60*100%=50%
(6-4)/4*100%=50%
20/40*100%=50%
5/50*100%=10%
7/10*100%=70%
(60-12)/60*100%=80%

Do me a favor. The sum of cubes of three continuous natural numbers in the science class of grade two in senior high school can be divided by 9. Use mathematical induction to calculate

If n ^ 3 + (n + 1) ^ 3 + (n + 2) ^ 3 can be divisible by 9 for any n, n ^ 3 + (n + 1) ^ 3 + (n + 2) ^ 3 = (n ^ 3 + 3N ^ 2 + 3N + 1) + (n + 2) ^ 3 + ((n + 1) ^ 3 + 6 (n + 1) ^ 2 + 1

Negative root 121 + root 2 and 1 / 4 minus root 36 + triple root minus 0.125

= -11+3/2-6+0.5
= -17 +2
= -15

Look_____ the numbers below and write the numbers out _____ words.

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The equation passing through (1, - 1, - 1) and parallel to the plane 3x-4y + 5z-8 = 0

Because the parallel plane equation is 3x-4y + 5Z + k = 0
Bring in the point (1, - 1, - 1), get k = - 2
So the parallel plane equation is 3x-4y + 5Z = 2

An extension of a system of linear inequalities with one variable
Known inequality system {3 (2x-1) 3 - (x-1) / 4
When a takes the minimum value, find the algebraic formula A ^ 2008 + 1 / A ^ 2009

3(2x-1)1.2
one point two

Mode and median of a set of data 30,25,40,20,60,50,30,50,30
Mode of a set of data 7,6,9,7,8,9,7,5,6

Mode [30], median [30] of a set of data 30,25,40,20,60,50,30,50,30
Mode of a set of data 7,6,9,7,8,9,7,5,6

How to calculate 986 * 89-987 + 88
Please support me. Thank you

986*88+986-987+88=88*（986+1）-1=86855

Storybooks are a quarter more than science and technology books, and storybooks are [] of science and technology books, and the ratio of science and technology books to storybooks is []
happy

Five quarters
4：5