Answer:
$31.50
Step-by-step explanation:
3j = $94.50
j = 94.50 / 3
j = $31.50
Answer: -2
Step-by-step explanation:
Answer:
A book is worth $1 and a DVD is worth $12.
Step-by-step explanation:
The equations (2 unknowns and two equations, d is for a DVD and b is for a book):
For David: 3d+4b=40
For Anna: d+6b=18
Now multiply the second equation with -3 and add to the first equation:
3d+4b=40
−3d−18b=−54
Combined equation: −14b=−14 and b=1 (means that each book is worth $1).
Now for DVD price, use the second equation:
d=18−6 or d=12 (means that each DVD is worth $12).
A book is worth $1 and a DVD is worth $12.
Answer:
see explanation
Step-by-step explanation:
(1)
Calculate the circumference (C) of the wheel
C = πd (d is the diameter )
= 3.14 × 8 = 25.12 cm
Now divide the distance travelled by the circumference.
times rotated = 12560 ÷ 25.12 ≈ 500
----------------------------------------------------------------
(2)
The area (A) of a circle is calculated as
A = πr² ( r is the radius )
Find r by using the circumference (C)
2πr = 50.24 ( divide both sides by 2π )
r = 50.24 ÷ 6.28 = 8 , then
A = 3.14 × 8² = 3.14 × 64 ≈ 200.96 ft² ( student 3 )
-----------------------------------------------------------------
(3)
C = πd = 3.14 × 30 = 94.2 ≈ 94 m
