Answer:
50 km/hr
Step-by-step explanation:
D = RT
Time for first part of trip = 80/60 = 4/3 hr.
Time for second part of trip = 20/30 = 2/3 hr.
total time for entire trip = 4/3 + 2/3 = 6/3 = 2 hr.
Total distance = 100 km
Average rate of speed for entire trip = 100/2 = 50 km/hr
1: 3/4 2: 6/8 I’m pretty sure is the answer sorry if I’m wrong
I believe it would be -16k^3 + 3v^4 - 9k^3 + 6v^4
Answer:
4688
Step-by-step explanation:
<h3>
Answer:</h3>
- <u>20</u> kg of 20%
- <u>80</u> kg of 60%
<h3>
Step-by-step explanation:</h3>
I like to use a little X diagram to work mixture problems like this. The constituent concentrations are on the left; the desired mix is in the middle, and the right legs of the X show the differences along the diagonal. These are the ratio numbers for the constituents. Reducing the ratio 32:8 gives 4:1, which totals 5 "ratio units". We need a total of 100 kg of alloy, so each "ratio unit" stands for 100 kg/5 = 20 kg of constituent.
That is, we need 80 kg of 60% alloy and 20 kg of 20% alloy for the product.
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<em>Using an equation</em>
If you want to write an equation for the amount of contributing alloy, it works best to let a variable represent the quantity of the highest-concentration contributor, the 60% alloy. Using x for the quantity of that (in kg), the amount of copper in the final alloy is ...
... 0.60x + 0.20(100 -x) = 0.52·100
... 0.40x = 32 . . . . . . . . . . .collect terms, subtract 20
... x = 32/0.40 = 80 . . . . . kg of 60% alloy
... (100 -80) = 20 . . . . . . . .kg of 20% alloy