The answer would be D. 200 - 20d.
This is because the question asks for pages left after reading for "d" (however many) hours. Since the book has 200 books, you'd subtract from that number since it's the "starting number" of pages. If he reads 20 pages per hour, you would multiply those together to get how many he has read, then subtract that number from 200, to get the amount of pages left.
I hope this helps!
Answer:
its 2 1/6 (B)
Step-by-step explanation:
Set up
Let the dimes = d
Let the pennies = p
Let the quarters = q
Equations
You cannot mean that the pennies and dimes have equal numbers. That would mean that each had 21.5 members. Now could you mean that the dime and penny amount could be the same with 43 coins that total 4.00. Four dollars means that you need 40 dimes alone. It must mean that you are including quarters.
p + d + p = 43 (1)
p = d (2)
p +10d +25q = 451 (3)
Note how this last equation = was derived. You have to multiply the dimes by 10 and he quarters by 100 and the total by 100 to get the numbers all in pennies.
Put the results of 2 into 1.
2p + q = 43 (4)
You need to modify equation 3 as well.
p + 10p + 25q = 451
11p + 25q = 451 (5)
Solve the new equations
2p + q = 43 (4)
11p + 25q = 451 (5)
Multiply 4 by 25
25(2p- + q = 43)
50p + 25q = 1075 (6) Subtract (5) from (6)
<u>11p + 25q = 451
</u>39p = 624 Divide by 39
p = 624 / 39
p = 16
Since the pennies and dimes are equal there are 16 dimes
p + d + q = 43
16 + 16 + q = 43
32 + q = 43
q = 11
Check
16 + 10*16 + 11*25 = ?
16 + 160 + 275 = ?
451 = ?
Nice problem. Thanks for posting.
Answer:
Step-by-step explanation:
abc = 1
We have to prove that,
We take left hand side of the given equation and solve it,
Since, abc = 1,
and c = 
By substituting these values in the expression,
Which equal to the right hand side of the equation.
Hence,
Answer:
x= 90-60
x=30
Step-by-step explanation:
