19.计算,怎样简便就怎样算
($\frac{1}{12}$+$\frac{1}{2}$-$\frac{5}{12}$)÷$\frac{1}{12}$ | 1$\frac{1}{4}$×25+25×$\frac{3}{4}$-1÷$\frac{1}{25}$ | 3×($\frac{2}{15}$+$\frac{1}{12}$)-$\frac{2}{5}$ |
(1$\frac{1}{8}$÷6+2$\frac{7}{8}$×$\frac{1}{6}$)÷(2-1$\frac{1}{3}$) | $\frac{7}{13}$×$\frac{3}{4}$+$\frac{3}{4}$×$\frac{6}{13}$ | $\frac{3}{7}$÷$\frac{7}{11}$+$\frac{4}{7}$÷$\frac{7}{11}$ |
18.a是一个大于零的自然数,那么下列各式中得数最大的是( )
A. | a×56 | B. | a÷56 | C. | 56÷a | D. | 56×a |
17.比80的38.75% 少8的数是( )
0 158225 158233 158239 158243 158249 158251 158255 158261 158263 158269 158275 158279 158281 158285 158291 158293 158299 158303 158305 158309 158311 158315 158317 158319 158320 158321 158323 158324 158325 158327 158329 158333 158335 158339 158341 158345 158351 158353 158359 158363 158365 158369 158375 158381 158383 158389 158393 158395 158401 158405 158411 158419 199269
A. | 1312 | B. | 1612 | C. | 7 | D. | 23 |