When multiplying decimals how do you know where the decimal goes

Solve the equation using the given values: x= -2.5; y= -7.51. 2xy + 2x²

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics

Item 1 solve for s. s+24=90 −114 −66 66 114