Answer:
20 gallons were used from the tank with the octane rating of 80.
Step-by-step explanation:
Given : One tank of gasoline has an octane rating of 140 and another tank of gasoline has an octane rating of 80. To obtain a mixture of 60 gallons with an octane rating of 120.
To find : How many gallons should be used from the tank with the octane rating of 80?
Solution : Let x be the volume of gas whose octane rating is 140 and
y be the volume of gas whose octane rating is 80.
Then, we form the equation as:
(1) 
or 
.........[3]
(2) 
Now multiply equation (2) by 4
...........[4]
Subtract (4) from (3)
Put x in equation [4] we get,
Therefore, x=40 and y=20
So, 20 gallons were used from the tank with the octane rating of 80.
Answer:
The experimental probability of the coin landing tails-side up is <u>60</u><u>%</u><u>.</u>
Step-by-step explanation:
The probability of it landing heads up is 4/10. You can use 4/10 to find how many times it landed on tails.
10/10 - 4/10= 6/10 now convert 6/10 into a percentage, 60/100=<u>60%</u>
Answer:
you added 6
Step-by-step explanation:
how the number order goes.
For the first draw, the probability of an ace is ( 4 / 52 ).
Now there are only 51 cards left in the deck.
For the second draw, the probability of a king is ( 4 / 51 ).
The probability of both events is
(4/52) (4/41) = (16/2,652)
Divide top and bottom by 4:
(16/2,652) = <em>4/663</em> . That's <em>choice-C </em>.
Its a prime number because 29 goes in to 10 numbers
