We have been given a number 75 and we are supposed to rewrite it using a different way. Since the given number has been written in standard notation, we can write it using scientific notation.
We know that we can write a standard number in scientific notation by moving the decimal point to the left or right and making corresponding changes to the exponent of 10. In this case, we will move the decimal point to the left by one place and raise the exponent of 10 by 1. Therefore, we get the required number in a different notation (scientific notation) as .
You would do 0.25x (x is the unknown total number)=19. It is because of is a multiply sign, so 0.25*x=19. Divide both sides by 0.25 and you get 76 as your answer.