3a+18+4a = 7a+18
12x+4y
45x
Answer:
102 ≤ heart rate ≤ 183.6
Step-by-step explanation:
... lower limit ≤ heart rate ≤ upper limit
Put 16 where "a" is and do the arithmetic.
... lower limit = 0.5(220 -16) = 102
... upper limit = 0.9(220 -16) = 183.6
Then the inequality is ...
... 102 ≤ heart rate ≤ 183.6
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<em>Comment on the problem</em>
There is nothing to "solve" here. One only needs to evaluate the limits.
You would need 24 machines
Because 1 machine makes 5 envelopes per minute so simultaneously 24 machines can make 120 envelopes per minute.
I'll use the same notation as the other one:
3(y-6)<4(y+5)
I'm going to clean this up a bit by distributing:
3y-18<4y+20
Now, subtract 3y from both sides:
-18And now, subtract 20:
-38So y is greater than or equal to -38
Hope this helps!