Answer:
He received 10 dimes and 15 quarters.
Step-by-step explanation:
Dimes = $0.10
Quarters = $0.25
Variable x = dimes
Variable y = quarters
Create a pair of linear equations:
0.10x + 0.25y = 4.75
x + y = 25
Isolate any variable, using an equation of your choice:
x + y = 25
x = 25 - y
Plug in this new value of x into the other equation:
0.10(25 - y) + 0.25y = 4.75
Use the distributive property:
2.5 - 0.10y + 0.25y = 4.75
Combine like terms:
2.5 + 0.15y = 4.75
Isolate variable y:
0.15y = 2.25
y = 15
Plug in the value of y into any equation:
x + y = 25
x + 15 = 25
Isolate variable x:
x = 10
A word to the wise: It's <span> f(x)=125(0.9)^x, where ^ represents exponentiation.
In this case the ave. value over the interval [11, 15] is
125(0.9)^15 - 125(0.9)^11
------------------------------------- = (125/4) [ 0.9^15 - 0.9^11)
15 - 11 = (31.25) [ 0.2059 - 0.3138 ] = a negative result
= (31.25)(-0.1079) = -3.372 (av. r. of c.
over the interval [11,15] )
Do the same thing for the time interval [1,5]. Then compare the two rates of change.</span>
Answer:
10k.
Step-by-step explanation:
1) if for the 1st position can be used 0-9 digits (10 digits), for the 2d - 0-9 digits, for the 3d - 0-9 digits and for the 4th - 0-9 digits, then
2) the required number of pwd is: 10*10*10*10=10⁴=10000.
Answer:
72 in. squared
Step-by-step explanation:
12 times 6 = 72
Think of it this way:
_ _ _ (3 digit number)
for the first blank you could have 7 possibilities
for the second blank you could have 6 possibilities
for the third blank you could have 5 possibilities
because each time you fill in a blank one number is removed from the list of possibilities
7×6×5=210. there are 210 possibilities
