If a concrete mix contains 1-1/2 cubic feet of gravel, 1/2 cubic foot of water, 1 cubic foot of cement, and 2 cubic feet of sand, what percentage of the mix is
sand?

The correct answer is "50%".

Step-by-step explanation:

The given values are:

Gravel,

=

Water,

=

Cement,

= 1

Sand,

= 2

Now,

The total mixture will be:

=

By substituting the values, we get

=

=

=

hence,

The percentage of sand will be:

=

=

= %

b. 6

step-by-step explanation:

we are given the table representing an exponential function.

we can see from the table that, as x is increasing, the value of y is increasing in the power of 6.

i.e. the following relation is obtained,

x = 1, y = 6

x = 2, y = 36 =

x = 3, y = 216 =

x = 4, y = 1296 =

x = 5, y = 7776 =

so, the geometric series obtained is .

thus, the common ratio is given by = = 6.

hence, the common ratio is 6.

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have