Answer:
The total change in the amount of money in my account is $ 9.60
Step-by-step explanation:
Given:
Amount of money deposited each week, 
Amount of money withdrawn each week, 
∴ Amount of money deposited in 4 weeks, 
∴ Amount of money withdrawn in 2 weeks, 
Now, amount of money left in the account is the difference of the two amounts.
So, amount left = 
Therefore, the total change in the amount of money in my account is given as:
Total change = Initial amount after 4 weeks - Final amount in the account.
Total change = $ 50 - $40.4 = $ 9.6
Answer:
5.097
Step-by-step explanation:
The mat adds 3 inches to each side, so the length would be 3+20 = 23 inches. The width would become 3 + 9 = 12 inches.Area = Length x width:
23 x 12 = 276 square inches
Answer:
Ratio = 
Step-by-step explanation:
Volume of Sphere is given by the formula:
Where
V is the volume
and
r is the radius
Original Volume, given r = 3, would be:
Increased snowball volume:
Radius increased 0.25 per second, he spent 4 seconds, so radius increase:
0.25 * 4 = 1 cm
New radius = 3 + 1 = 4 cm
New Volume would be:
Ratio of New Volume to Original would be:
This is the ratio for current volume to original volume.
Answer:
See below.
Step-by-step explanation:
1. (1 / 2)[cos(a – b) – cos(a + b)]
= 1/2 ( cosa cosb + sina sinb - (cosa cosb - sina sinb)
= 1/2 ( cosa cosb - cosa cos b + sina sinb + sina sinb)
= 1/2 ( 2 sina sinb)
= sina sinb.
(I used the 2 identities cos(a - b) = cosa cosb + sina sinb) and
cos (a + b) = cosa cosb - sina sinb.)
2. sin (π/2 - x) = sin (π/2) cos x - cos(π/2) sin x
= 1 * cos x - 0 * sinx
= cosx - 0
= cos x.
(I used the identity sin(a - b) = sina cosb - cosa sinb
and the fact that sin(π/2) = 1 and cos (π/2) = 0. )
