The final price is the cost plus the tax.
Since we know the tax and a percent, we can write this as
T = C(1+r)
T = what Graham paid = $87.45
C = cost before tax
r = tax rate expressed as a decimal = .40
Plugging in what we know
87.45 = C (1+.4)
87.45 = C(1.4)
Divide both sides by 1.4
C = $62.46
Answer: 50.24
Area of a circle is pi times r^2
The r is 1/2 the d
So 8/2 = 4
Pi times 4^2= 50.24
Answer:
Saw this question before. The answer is Anita' square.
Square has only four sides while the others more than four so make sense for the square to have longer sides
Let's focus on 0.7*0.8 for now.
Start by drawing a large square. Cut this figure into 10 rows and 10 columns. So this means you'll have 10*10 = 100 little squares.
Now highlight the first 7 rows. Shade in all 70 squares (7*10 = 70)
Starting on the left side, highlight the first 8 columns. You'll shade in 80 squares (8*10 = 80)
Use different colors for your highlighting or somehow indicate different shading styles. This way you can see the overlapping region. The overlapping region consists of 56 squares (7 rows, 8 columns ---> 7*8 = 56 little squares)
Each little square represents 0.01, so having 56 of them means we have 0.56
This shows that 0.7*0.8 = 0.56
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How is this different if we had 1.7*0.8? Well we can break 1.7 into 1+0.7 to have
1.7*0.8 = (1+0.7)*0.8
1.7*0.8 = (1)*0.8+(0.7)*0.8
1.7*0.8 = (1*0.8)+(0.7*0.8)
The portion (0.7*0.8) was done earlier. That result was 0.56. So we just need to compute (1*0.8), which is simply 0.8; recall that 1 times any number is that number itself.
Now simply add 0.8 to 0.56 to get 1.36
So, 1.7*0.8 = 1.36
Each side of the board would have to be at least 36
