Answer:
12 years younger.
Step-by-step explanation:
Let Jan's age be J and Karyn's age be K.
Jan's age 8 years ago is 2/5 of Karyn's age 4 yeaRs from now.
=> 
=> 4K = 48 X 3
=> K= 36.
=> J= 24.
So Jan is 12 years younger.
Answer:
45
Step-by-step explanation:
AEF is a similar triangle to ABC. that means it has the same angles, and the sides (and all other lines in the triangle) are scaled from the ABC length to the AEF length by the same factor f.
now, what is f ?
we know this from the relation of AC to FA.
FA = 12 mm
AC = 12 + 28 = 40 mm
so, going from AC to FA we multiply AC by f so that
AC × f = FA
40 × f = 12
f = 12/40 = 3/10
all other sides, heights, ... if ABC translate to their smaller counterparts in AEF by that multiplication with f (= 3/10).
the area of a triangle is
baseline × height / 2
aABC = 500
and because of the similarity we don't need to calculate the side and height in absolute numbers. we can use the relative sizes by referring to the original dimensions and the scaling factor f.
baseline small = baseline large × f
height small = height large × f
we know that
baseline large × height large / 2 = 500
baseline large × height large = 1000
aAEF = baseline small × height small / 2 =
= baseline large × f × height large × f / 2 =
= baseline large × height large × f² / 2 =
= 1000 × f² / 2 = 500 × f² = 500 ×(3/10)² =
= 500 × 9/100 = 5 × 9 = 45 mm²
Answer:
78.54in²
Step-by-step explanation:
i used the formula
We know that
the Volume of a prism=a*b*c
a----> tall--------> 8 1/2 in=8.5 in
b-----> wide-----> 7 in
c-----> <span>thick-----> 2 1/2 in=2.5 in
therefore
V=8.5*7*2.5=148.75 in</span>³------------equal a 148 3/4 in³
the answer is the option <span>c 148 3/4 in³</span>
