论文部分内容阅读
1.近似数247.65与0.32的积为什么得79? 首先应该弄明白什么是有效数字。二个近似数,从左边第一个不是零的数字起,到右边截得的最后一个数字止,都叫做这个近似数的有效数字。如,近似数1.5有两个有效数字1,5:近似数1.50有三个有效数字1,5,0;近似数0.15有两个有效数字1,5。 现在我们再来说两个近似数相乘。在通常情况下,两个近似数相乘,有效数字最少的那个近似数有多少个有效数字,积也最多只能有同样多个有效数字。因为通过运算最后能够确定(考虑到不受近似数后被截取的数字的影响)的数字至多只能有和有效数字最少的那个近似数同样多个有效数字。
1. Why the approximation of the product of 247.65 and 0.32 79? First of all, we should understand what is a significant figure. The two approximations, starting with the first non-zero figure on the left and ending at the right, are all called significant figures for this approximation. For example, an approximate number of 1.5 has two significant figures of 1,5: an approximate number of 1.50 has three significant figures of 1,5,0; and an approximate number of 0.15 has two significant figures of 1,5. Now let us repeat the multiplication of two approximations. Under normal circumstances, the multiplication of two approximations, the number of approximations with the least significant figures, and the accumulation of up to only the same number of significant figures. Because the number that can be finally determined by the operation (taking into account the effects of the digits that are not intercepted by the approximation) can be at most as many significant digits as the one with the least significant digits.