Standard Form Operations Sprint

About Standard Form Operations Sprint

Standard Form Operations Sprint covers the half of standard form our existing conversion game does not: doing arithmetic with it. Multiplying is two moves — multiply the mantissas, add the indices — and dividing is the same two moves in reverse. Neither is difficult, and students generally get both right. What they miss is the third move, which nobody thinks of as a move at all: re-normalising the result. Four times five is twenty, so multiplying four times ten to the seven by five times ten to the something produces twenty times ten to a power, and twenty is not a number that can sit in front of a power of ten in standard form. The mantissa has to be between one and ten, so twenty times ten to the seven becomes two times ten to the eight. A student who stops one step early has an answer that is numerically exactly right and is not in standard form, which means it is wrong for the purposes of the question and looks entirely correct to the person who wrote it. That un-normalised form is offered as an option in every round for precisely that reason. The other wrong options cover multiplying the indices instead of adding them, and landing one power out. Multiplication alone at the first two levels, with division joining from the third, where a mantissa below one forces normalisation in the other direction. Free, no sign-up, no advertising to children.