Sum 8 + 88 + 888 +. + 888.888 The last one has n eights It is represented by the sum with n

Sum 8 + 88 + 888 +. + 888.888 The last one has n eights It is represented by the sum with n

The original formula is 8 * n + 8 * 10 * (n-1) + +8*10^n
= 8*{n+(n-1)*10+… +10^n}
It's a difference sequence in brackets
=8/9（ 10^(n+2) /9 -10/9 -n ）

0.8, 0.88, 0.888

an=8/9[1-1/(10^n)]

The formula of 0 8 88 888 8888
What is the regular formula of 0 8 88 888 8888?

The nth number an = 8 × [10 ^ (n-1) - 1] / 9
10 ^ (n-1) is the N-1 power of 10
for example
The first number = 8 × [10 ^ (1-1) - 1] / 9 = 0
The second number = 8 × [10 ^ (2-1) - 1] / 9 = 8
The third number = 8 × [10 ^ (3-1) - 1] / 9 = 8

There are 3-5-12-7, which is equal to 24 by four far counts

((3*12)+-5)-7
(3*12)+(-5-7)
(3*12)-(7--5)
((3*12)-7)+-5
(3*(7--5))-12
-5+((3*12)-7)
(-5+(3*12))-7
-5+((12*3)-7)
(-5+(12*3))-7
-5-(7-(3*12))
(-5-7)+(3*12)
-5-(7-(12*3))
(-5-7)+(12*3)
((12*3)+-5)-7
(12*3)+(-5-7)
(12*3)-(7--5)
((12*3)-7)+-5
((7--5)*3)-12

2, 4, 10, 10 how to calculate is equal to 24

[2+（4÷10)]*10=24

How is 10.10.2.4 equal to 24

4 root plus 2 plus 10 plus 10
I'm not sure it's going to take root

Fill in the operation symbols, add, subtract, multiply, divide and bracket to make the equation hold. 5 5 15 equals 8 3 8 3 equals 24

5+5x1÷5=8x3÷8+3=2+4 5 x（5-1÷5）= 8 ÷ (3 - 8 ÷ 3)=24

How do two tens and two fours equal twenty-four

(10*10-4)/4=24

3 8 11 16 how is it equal to 24
Only four

(11*8-16)÷3=24

How do five sixes equal 24

①(6+6)×(6+6)÷6=24
②6×（6-6/6）-6=24
③