Answer:
8
Step-by-step explanation:
0) the basic formula is: L=v*t, where L - distance, v - speed/velocity; t - time;
1) if the person's speed in still water is 'v' and the speed of water is 5 (according to the condition), then the upstream speed is 'v-5' and the downstream speed is 'v+5';
2) according to the condition the upstream time and the downstream time are the same, it means t₁=t₂=t, where t₁=upstream time and t₂=downstream time;
3) according to the items above it is possible to make up the equation of the upstream travel: t(v-5)=3; ⇒ t=3/(v-5);
4) according to the items above it is possible to make up the equation of the downstream travel: t(v+5)=13; ⇒ t=13/(v+5);
5) if t=3/(v-5) and t=13/(v+5), then

Answer: it cost a customer $7.25 to buy five tulips and $10.5 to buy six roses.
Step-by-step explanation:
Let x represent the cost of 1 tulip.
Let y represent the cost of 1 rose.
The price of each tulip is the same and the price of each roses the same. One customer bought seven tulips and nine roses for $25.90. This means that
7x + 9y = 25.9 - - - - - - - - - - - - - - 1
Another customer bought for four tulips and eight roses for $19.80. This means that
4x + 8y = 19.8- - - - - - - - - - - - - - - 2
Multiplying equation 1 by 4 and equation 2 by 7, it becomes
28x + 36y = 103.6
28x + 56y = 138.6
Subtracting, it becomes
- 20y = - 35
y = - 35/ - 20
y = 1.75
Substituting y = 1.75 into equation 2, it becomes
4x + 8 × 1.75 = 19.8
4x + 14 = 19.8
4x = 19.8 - 14 = 5.8
x = 5.8/4
x = 1.45
The cost of 5 tulips would be
1.45 × 5 = $7.25
The cost of 6 roses would be
1.75 × 6 = $10.5
- 300
- 59
- 4
- 78
ok so put it like that and it will be correct.............................................................................(long pause)........................................................................................................... (thinks) I think that the right answer.
Answer:
2.06
Step-by-step explanation:
lmk if u need an explanation