How to do 55 times 88 with simple calculation aaaa

How to do 55 times 88 with simple calculation aaaa

55×88
=（50+5）×（80+8）
=50×（80+8）+5×（80+8）
=50×80+50×8+5×80+5×8
=4000+400+400+40
=4840

Calculation: (1 + 3 + 5 +...) +1989）-（2+4+6+… +1988）=______ ．

（1+3+5+… +1989）-（2+4+6+… +1988), = (1 + 1989) × [(1989 + 1) △ 2] × 2 - (2 + 1988) × (1988 △ 2) △ 2, = 995 × 995-995 × 994, = 995 × (995-994), = 995

One fourth of the coal was burned in the first day, one third in the second day, two thirds in the third day, and 88 tons remained in the third day. How many tons were burned in the first day

Total x tons
The first day burned X / 4 tons
The second day burned one third of the first day, and the second day burned X / 12 tons
The third day burned two-thirds of the second day, and the third day burned X / 18 tons
x=x/4-x/12-x/18=88
11x/18=88
X = 144 tons
The first day, it burned X / 4 = 144 / 4 = 36 tons

The simple operation of two thirds plus two ninths plus two 27ths plus two eighties

2/3+2/9+2/27+2/81
=54/81+18/81+6/81+2/81
=80/81
Wuliangshou Buddha, the Buddha said that the sea of bitterness is endless, looking back is the shore!
Benefactor, I see your bones are strange,
He is a man of noble bearing and wisdom,
He is a unique talent in the Wulin
If you devote yourself to study, you will become a great tool in the future,
I have a little test, please click next to the answer
"Choose as satisfactory answer"

How to do 25 × 16 + 14 × 15 with simple calculation

15×（16+14）+160

4 / 9 * 22 and 13 / 15 + 16 * 1 / 9 + 2 / 9 * 14 / 15 need simple calculation

4 / 9 × 22 and 13 / 15 + 16 × 1 / 9 + 2 / 9 × 14 / 15 = 4 / 9 × (22 and 13 / 15 + 4 + 7 / 15) = 4 / 9 × (27 + 1 / 3) = 4 / 9 × 27 + 4 / 9 × 1 / 3 = 12 and 4 / 27

A simple calculation method of 200 - (15-16) - (14-15) - (13-14) - (12-13)

200-15+16-14+15-13+14-12+13
Eliminate the numbers with different symbols, and the last one is
200+16-12=204

The simple calculation of 25 × 16 × 15 should have the formula of separation

25×4×（4×15）=100×60=6000

How to calculate (745-25 × 16) △ 15 easily

（745-25×16）÷15=745-25*4*4）÷15=（745-100*4）÷15=345÷15=23

What is 14 * 15 equal to 210
I forgot who's going to ride and who's going to beg. It's all numbers

（10+4）*15=150+60=210