Solution equation: 1.98% x = (1000-x) 2.15 ‰ x12x (1-20%)

Solution equation: 1.98% x = (1000-x) 2.15 ‰ x12x (1-20%)

2.15‰x12x（1-20%）
=0.00215×12×0.8
=0.02064
0.0198X=(1000-X)×0.02064
1980X=2064000-2064X
4044X=2064000
X≈510.386.

Solve the equation 1000 × (1 + x) ^ 8 = 2000

1000×(1+x)^8=2000
(1+x)^8=2000/1000=2
Open root octave of (1 + x) = 2
Open root octave of x = 2-1

How to round up at random in excel? For example, I want to generate numbers less than 1000 and more than 800 at random, but the single digit is required to be 0, such as 850, 960, 980

=randbetween(81,99)*10
perhaps
=ROUND(RAND()*200+800,-1)

How to add brackets when 35 + 15 times 40-20 = 1000

(35+15)×(40-20)=1000