Answer:
4
Step-by-step explanation:
1. if the mass of coffee worth $10 is 'x', then its worth is 10x, and the worth of the mixture is 5(x+20);
2. using the previous item it is possible to write the next equation:
5(x+20)=4*20+10*x; ⇒ x=4.
3. the required mass is 4 pounds.
9x + 1 = 7x - 9
-7x. -7x
2x + 1 = -9
-1. -1
2x = -10
Divide by 2
x = -5
The hand went around 7 numbers.
Answer:
-7/45
Step-by-step explanation:
First, find the lowest common denominator for 9 and 15. It's 45. Make both fractions over 45 by multiplying the top and bottom by the same number.

Since 15*3=45, multiply the top by 3 also. Since 9*5=45, multiply the top by 5 also.

Combine the fractions
Answer in lowest terms
Answer:
x+ x+1 + x+2 = 30
3x+3 =30
Step-by-step explanation:
Let x be the smallest integer
x+1 be the next smallest
x+2 be the third
x+ x+1 + x+2 = 30
Combine like terms
3x+3 =30