Matt spent 3/10 of his allowance on projects, 2/5 on snacks, and 2/3 of the remainder on books. What is the fraction of his allowance was spent on books?

yes. we do proportions in probabilities.

ummm seems that u didnt post the attachement !

explanation:

infrared radiation has wavelength in the range between 700 nm and 1 mm. lets' convert these values into scientific notation, keeping in mind that:

let's start from the lower value, we have:

(we moved the dot two places to the left, so we increased the exponent by 2 units, from -9 to -7)

the higher value is:

so, the range of wavelength of infrared radiation is: