Alice counted 7 cycle riders and 19 cycle wheel going past her house. How many tricycle were there?
回答 (13)
2020-08-02 2:23 pm
Method 1: Linear equation with one unknown
Let n be the number of tricycles.
Then, the number of bicycles = (7 - n)
Total number of wheels:
3n + 2(7 - n) = 19
3n - 14 - 2n = 19
n = 5
There were 5 tricycles.
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Method 2: Simultaneous equations with two unkowns
Let x be the number of tricycle, and y be the number of bicycle.
x + y = 7 …… [1]
3x + 2y = 19 …… [2]
[1] * 2:
2x + 2y = 14 …… [3]
[2] - [3]:
(3x + 2y) - (2x + 2y) = 19 - 14
n = 5
There were 5 tricycles.
Let n be the number of tricycles.
Then, the number of bicycles = (7 - n)
Total number of wheels:
3n + 2(7 - n) = 19
3n - 14 - 2n = 19
n = 5
There were 5 tricycles.
====
Method 2: Simultaneous equations with two unkowns
Let x be the number of tricycle, and y be the number of bicycle.
x + y = 7 …… [1]
3x + 2y = 19 …… [2]
[1] * 2:
2x + 2y = 14 …… [3]
[2] - [3]:
(3x + 2y) - (2x + 2y) = 19 - 14
n = 5
There were 5 tricycles.
2020-08-02 2:30 pm
Assuming only numbers of bicycles b and tricycles t present.
2b + 3t = 19
b + t = 7
tricycles t = 5
2b + 3t = 19
b + t = 7
tricycles t = 5
2020-08-02 2:17 pm
Six tricycles and a unicycle.
2020-08-03 12:27 pm
My guess is 7 bicycles and 5 tricycles. But nobody thought of unicycles or quadricycles.
2020-08-03 7:11 am
if bicycles, and tricycles: 2..... bicycles = 4 wheels.....5 tricycles= 15 wheels...…, 4 wheels plus 15 wheels= 19 wheels......answer is 5
2020-08-02 4:49 pm
If all 7 were on bicycles it would be 14 wheels, so the 5 extra wheels must be on tricycles.
2020-08-05 10:46 pm
By common sense, there are 2 kinds of cycles on the road; one is the bicycle the other one is tricycle. So, let
b=the number of bicycles
t=the number of tricycles
b+t=7
2b+3t=19
=>
2(7-t)+3t=19
=>
14-2t+3t=19
=>
t=5.
b=the number of bicycles
t=the number of tricycles
b+t=7
2b+3t=19
=>
2(7-t)+3t=19
=>
14-2t+3t=19
=>
t=5.
2020-08-04 3:01 am
In doing this kind of homework problem, state your assumptions.
- There are only bicycle and tricycle riders. No uniccles, adult 4-wheel pedal carts.
- There is one, and exactly one, rider per cycle. No tandem bikes, no riderless self-riding bicycle.
Then if b is the number of bicycles, and t the number of tricycles,
b + t = 7 ; total number of riders
2b + 3t = 19 ; bike has 2 wheels, trike has 3
You now have 2 equations in 2 unknowns. If you need help in proceeding, I'm sure another answer will spell it out for you.
- There are only bicycle and tricycle riders. No uniccles, adult 4-wheel pedal carts.
- There is one, and exactly one, rider per cycle. No tandem bikes, no riderless self-riding bicycle.
Then if b is the number of bicycles, and t the number of tricycles,
b + t = 7 ; total number of riders
2b + 3t = 19 ; bike has 2 wheels, trike has 3
You now have 2 equations in 2 unknowns. If you need help in proceeding, I'm sure another answer will spell it out for you.
2020-08-03 9:18 pm
Alice counted 7 cycle riders and 19 cycle wheels going past her house.
How many tricycles were there?
b + t = 7
2b + 3t = 19
t = 5
How many tricycles were there?
b + t = 7
2b + 3t = 19
t = 5
2020-08-03 8:40 am
2*2+5*3=4+15= .19
2020-08-02 8:42 pm
We would need to know the number of unicycles and tandems.
2020-08-02 7:40 pm
5 tricycles and 2 bicycles
2020-08-03 10:14 am
6 as 3X6 is 18 The seventh rider was on a Unicycle.
收錄日期: 2021-04-24 07:58:29
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