multiply-divide

基本解釋

Simple math tool to practice add, subtra - Simple math tool to practice add, subtract, multiply, and divide.
簡(jiǎn)單的數(shù)學(xué)工具用來(lái)執(zhí)行加，減，乘，除運(yùn)算。
Where they fared less well was number ability (how quickly you can multiply, add, subtract and divide) and perceptual speed - how fast you can push a button when prompted.
年長(zhǎng)者表現(xiàn)不太好的方面則是：（數(shù)字能力加減乘除運(yùn)算的速度）以及感知速度——聽(tīng)到指令按下按鈕的速度。
So, the number of nuclei, 119 if we were to sit and count these as well, is 119. So, we'll multiply that by just pi, r squared, to get that cross-section, and divide all of that by 1 .
如果你們數(shù)的話，原子核的數(shù)是，我們用它乘以πr的平方，得到橫截面積，除以1。

So, the number of nuclei, 119 if we were to sit and count these as well, is 119. So, we'll multiply that by just pi, r squared, to get that cross-section, and divide all of that by 1 . 39 meters squared.
如果你們數(shù)的話，原子核的數(shù)是，我們用它乘以πr的平方，得到橫截面積，除以1。39平方米。
麻省理工公開(kāi)課 - 化學(xué)原理課程節(jié)選