Answer: 7.5
Step-by-step explanation: -2/5= -0.4 so -3/-0.4=7.5
Answer:
9 square kilometers
Step-by-step explanation:
Let's round the width to 2.0 kilometers, and round the length to 4.5 kilometers.
We know that area is length times width, so
A = lw
A = 2.0*4.5
<u>A = 9.0 square kilometers</u>
If we do this on the calculator, it's around 9.36 square kilometers, so our estimate was good.
Answer:
Wyzant
ALGEBRA WORD PROBLEM
Dorian S. asked • 06/28/17
THREE LINEAR EQUATIONS WITH THREE VARIABLES
A chemist has three different acid solutions. The first acid solution contains 15% acid, the second contains 25%,
and the third contains 70%. He wants to use all three solutions to obtain a mixture of 40 liters containing 45%
acid, using 2 times as much of the 70% solution as the 25% solution. How many liters of each solution should be used?
How to set up as three linear equations to find the answer?
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1 Expert Answer
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Arthur D. answered • 06/28/17
TUTOR 4.9 (67)
Forty Year Educator: Classroom, Summer School, Substitute, Tutor
ABOUT THIS TUTOR ›
set up 2 equations
the first equation...
15%*x+25%*y+70%*2y=45%*40
0.15x+0.25y+1.4y=0.45*40
0.15x+1.65y=18
multiply all terms by 100
15x+165y=1800
divide all terms by 15
x+11y=120
the second equation...
x+y+2y=40
x+3y=40
x=40-3y
substitute into the first equation x+11y=120
40-3y+11y=120
40+8y=120
8y=120-40
8y=80
y=80/8
y=10 liters
x+3*10=40
x+30=40
x=40-30
x=10 liters
10 liters of 15%, 10 liters of 25%, and 20 liters of 70%
check:
10*15%=1.5
10*25%=2.5
20*70%=14
1.5+2.5+14=18
18/40=9/20=45/100=45%
45%*40=18
hope it helps
please mark brainliest
Answer:
74 inches
Step-by-step explanation:
If his cousin is 40 inches tall, and Zach is 6 inches less than twice his height, solve for 40*2-6, which is 74.
Answer:
6,000 ft
Step-by-step explanation:
3,000 x 2 = 6,000
