9/16,-9/8,9/4,-9/2, what is the next missing number in the sequence above? hurry need asap

Hello from MrBillDoesMath!

-18

Discussion:

I immediately noticed that  9/16 times -2 is the next term (-9/8) and  -9/8 times -2 is, again, the next term (9/4). Continuing like this gives

(9/4) * (-2) = - 9/2

(-9/2)*(-2)  = 9

9 * (-2) = -18

which is the desired answer

Thank you,

MrB

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.

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: