A) .10 d + .25 q = 7.75
B) d + q = 40
Multiplying B) by -.10
B) -.10d -.10q = -4.0
Then adding this to A)
A) .10 d + .25 q = 7.75
.15q = 3.75
Quarters = 25
Therefore, dimes = 15
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Double-Check
A) .10 d + .25 q = 7.75
A) .10 * 15 d + .25 * 25 = 7.75
A) 1.50 + 6.25 = 7.75
Correct!!
Answer:
Number of pineapples = 10
Number of pears = 10 + 9 = 19
Number of kiwis = 10 - 2 = 8
Step-by-step explanation:
Money = $ 13.5
Cost of a pear = $ 0.5
Cost of a pineapple = $ 1.5
Cost of a kiwi = $ 0.3
let the number of pineapple = p
Number of pears = p + 9
Number of kiwis = p - 2
Cost is
0.5 (p + 9) + 0.15 p + 0.3 (p - 2) = 13.5
0.5 p + 4.5 + 0.15 p + 0.3 p - 0.6 = 13.5
0.95 p = 9.6
p = 10
So, number of pineapples = 10
Number of pears = 10 + 9 = 19
Number of kiwis = 10 - 2 = 8
Answer:
You will have 128 orange marbles
Step-by-step explanation:
Set this up as an equation
Variable x = number of orange marbles
3/8 = 48/x
Cross multiply
3 × x = 8 × 48
3x = 384
Divide both sides by 3 to isolate the variable
3x ÷ 3 = 384 ÷ 3
1x = 128
x = 128
128 orange marbles
Check work:
Substitute the variable x for the answer
3/8 = 48/128
Cross multiply
3 × 128 = 8 × 48
384 = 384
If the numbers equal, the answer is correct
9514 1404 393
Answer:
a) 600
b) see below
c) 1.26 hours
Step-by-step explanation:
a) The value of y when x=0 is the coefficient of the exponential term:
y = 600·3^(-0) = 600·1 = 600
There were 600 atoms to start.
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b) see attached for a graph
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c) The graph shows 150 atoms at t = 1.26, about 1.26 hours after the start of time counting.
If you want to find that value algebraically, substitute for y and solve for x. Logarithms are involved.
150 = 600·3^(-x)
150/600 = 3^(-x)
log(1/4) = -x·log(3)
x = -log(1/4)/log(3) = log(4)/log(3) ≈ 1.2618595
After about 1.26 hours, there were 150 atoms.
Answer:
=> 2.7 × 10³ × 8 × 10² / 4 × 10^-6
=> 2.7 × 8 × 10^3+2+6 /4
=> 5.4 × 10¹¹
5.4 × 10^11
