Answer:
£1638.40
Step-by-step explanation:
Step one:
Given data
A car costs £5000 when new
Each year the value decreases by 20%.
Step two:
let us compute the worth in the next 5 years
year 1
worth= 5000- 0.2*5000
worth= 5000-1000
worth= £4000
year 2
worth= 4000- 0.2*4000
worth= 4000-800
worth= £3200
year 3
worth= 3200- 0.2*3200
worth= 3200-640
worth= £2560
year 4
worth= 2560- 0.2*2560
worth= 2560-512
worth= £2048
year 5
worth= 2048- 0.2*2048
worth= 2048-409.6
worth= £1638.40
The person is wrong because after 5 years the car is worth £1638.40
Volume of a volleyball (a sphere) = 4/3πr³
= 4/3π(11.4)³
= 1975.392π
= 6210 cm³ (to 3 significant figures)
The volume of a volleyball with a radius of 11.4 cm will be 6210 cm³.
The answer is 7x = 6(x + 15)
x - Jim's rate
y - Pete's rate
<span>Jim completed half the floor in 7 hours: 7x = half of the floor
</span><span>Pete completed the other half of the floor in 6 hours: 6y = half of the floor
So: 7x = 6y
</span><span>Pete can lay 15 more tiles per hour than Jim: y = x + 15
</span>7x = 6y
y = x + 15
Substitute the second equation into the first one:
7x = 6(x + 15)
Answer:
7 . 4 + 6 - 12 : 4 = 31
Step-by-step explanation:
* To solve this problem lets revise the order of operations in
mathematics
- The operations are:
# Addition
# Subtraction
# Multiplication
# Division
# Exponentiation
# Grouping ⇒ Parenthesis or brackets
- The order of these operations is:
# Parenthesis
# Exponents
# Multiplication and Division which comes first from left to right
# Addition and Subtraction which comes first from left to right
- There is a word made from the first letter of each operation
PEMDAS to remember the order of operations
* Lets solve the problem
∵ 7 . 4 + 6 - 12 : 4
∵ The (.) means multiply the numbers
∵ The symbol (:) means divided the numbers
∴ At first multiply 7 by 4 and divide 12 by 4
∴ (7 × 4) + 6 - (12 ÷ 4)
∴ 28 + 6 - 3
∵ Addition comes before subtraction from the left
∴ (28 + 6) - 3
∴ 34 - 3 = 31
∴ 7 . 4 + 6 - 12 : 4 = 31