<span>The method of solving "by substitution" works by solving one of the equations (you choose which one) for one of the variables (you choose which one), and then plugging this back into the other equation, "substituting" for the chosen variable and solving for the other. Then you back-solve for the first variable.</span>
Answer: 80%
80,000 = 100%
20,000 = 20%
100% - 20% = 80%
Always convert the main number into 100 and follow through with the other numbers
Work=speed times time (my equation to help me figure it out)
ok, 10 men take 84 days to complete a job
therefor, each man completes 1/10 of the job in 84 days
each man does 1/840 of the job per 1 day
so, if we had 5 more, or 15 men
15 times 1/840 times xdays=1 job complete
15/840 times xdays=1job
times both sides by 840/15
xdays=840/15
xdays=56
56 days it would take
7/10 of 80 is 56
4/5 of 80 is 64
3/4 of 80 is 60
5/8 of 80 is 50
1/2 of 80 is 40
1/4 of 80 is 20
1/10 of 80 is 8
1/8 of 80 is 10
to work these out divide the number by the denominator (bottom number) and multiply by the numerator (top number)
Answer: He bought 7 pens.
Step-by-step explanation:
21/3 = 7
