-14×3/4-0.34×3/7+1/4×(-14)+4/7×-0.34

-14×3/4-0.34×3/7+1/4×(-14)+4/7×-0.34

-14×3/4-0.34×3/7+1/4×(-14)+4/7×-0.34
=-14×（-3/4-1/4）-0.34×（3/7+4/7）
=-14-0.34
=-14.34

-14 × 3 / 4-0.34 × 3 / 7 + 1 / 4 × (- 14) + 4 / 7 × - 0.34 (simple)

-14×3/4-0.34×3/7+1/4×(-14)+4/7×-0.34
=-14x(3/4+1/4)-0.34x(3/7+4/7)
=-14-0.34
=-14.34

1、 7,14,23,34,（ ）2、 2/7,3/11,1/3,7/19,（ ）3、1,2,4,7,12,（ ）

1. 7,14,23,34, (47) the difference is the odd sequence of 7,9,11,13 adjacent. The equal difference is 2, so fill in 472, 2 / 7,3 / 11,1 / 3,7 / 19, (11 / 23) can be: 2 / 7,3 / 11,5 / 15,7 / 19, (11 / 23) the denominator equal difference is 4, so the numerator is 23, the prime sequence of 2,3,5,7,11. Adjacent, so it is 113, 1,2,4,7,12, (20) the difference is 1,2,3,5,8, the first two terms add up to the third term,