3.8 + 4.29 + 2.1 + 4.2 what can be calculated simply should be calculated simply 3.8+4.29+2.1+4.2

3.8 + 4.29 + 2.1 + 4.2 what can be calculated simply should be calculated simply 3.8+4.29+2.1+4.2

It's too simple
3.8+4.29+2.1+4.2
=（3.8+4.2）+（4.29+2.1）
=8+6.39
=14.39

Simple calculation of 29 / 13 - (3 / 13 + 5 / 7) - 2 / 7

29/13-（3/13+5/7）-2/7
=29/13-3/13-5/7-2/7
=26/13-7/7
=2-1
=1

Simple calculation: 1 minus 3 points 1 plus 12 points 7 minus 20 points 9 plus 30 points 11 minus 42 points 13
1 minus 1 / 3 plus 7 / 12 minus 9 / 20 plus 11 / 30 minus 13 / 42
Simple calculation
It's a step

Split term method
1 minus 1 / 3 plus 7 / 12 minus 9 / 20 plus 11 / 30 minus 13 / 42
=1-1/3+1/3+1/4-1/4-1/5+1/5+1/6-1/6-1/7
=1-1/7
=6/7

How much is 1 / 8 * 9 + 1 / 9 * 10 + / 110 * 11 +... + / 99 * 100,

1/8*9+1/9*10+/110*11+...+/99*100
=(1/8-1/9)+(1/9-1/10)+...+(1/99-1/100)
=1/8-1/9+1/9-1/10+.+1/99-1/100
=1/8-1/100
=23/200;