Answer:
The rock will take about 4.5 seconds to reach the river
Step-by-step explanation:
* lets study the situation of the rock
- The rock is dropped means the initial velocity is zero
- The motion is free fall under earth gravity
- The rock dropped from a bridge 320 feet above the river
- The equation of the pathway is h = -16t² + 320
- When the rock reach to the ground the height will be zero
* Now lets substitute h by zero in the equation to find t
∵ h = -16t² + 320
∵ h = 0
∴ 0 = -16t² + 320 ⇒ add 16t² to both sides
∴ 16t² = 320 ⇒ divide both sides by 16
∴ t² = 320/16 = 20
∴ t² = 20 ⇒ take √ for both sides
∴ t = √20 = 2√5 ≅ 4.5 seconds
* The rock will take about 4.5 seconds to reach the river
Answer:
Step-by-step explanation:
Given
- Deposit = $10000
- Interest rate = 3.2% PA
- Interest type = compound
- Frequency = continuous
- Time = 6 years
Calculation
- Total = 10000*e^(rt) = 10000*e^(0.032*6) = $12116.71
area of rectangle= 8*13=104m^2
base of the Triangle= 13 -(4+4)=5
area of Triangle = 5*6/2=15m^2
area of shaded shape =104-15= 89m^2
Toby saves 30.30 money by buying 30 T-shirts at better price.
Step-by-step explanation:
Cost of pack of 5 T-shirts = 13.00 money.
Cost of pack of 2 T-shirts = 7.22 money.
Toby wants to buy total T-shirts = 30 T-shirts.
<u>Case 1 </u>:
For 30 T-shirts, If Toby buys in packs of 5 T-shirts then the number of packs he should buy = 30/5 = 6 packs.
The cost for six packs of 5 T-shirts = 6*13.00 = 78.00 money.
<u>Case 2 </u>:
For 30 T-shirts, If Toby buys in packs of 2 T-shirts then the number of packs he should buy = 30/2 = 15 packs.
The cost for 15 packs of 2 T-shirts = 15*7.22 = 108.30 money.
The money saved = 108.30 -78.00 = 30.30 money.
Therefore, The better price to buy 30 T-shirts is 78.00 money.