If \(x=-2.531\), what is the value of \(x^2\) rounded to 2 decimal places?
- \(-6.41\)
- \(-6.40\)
- \(6.40\)
- \(6.41\)
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If \(x=-2.531\), what is the value of \(x^2\) rounded to 2 decimal places?
\(D\)
\( x^2\) | \(=(-2.531)^2 \) | |
\(=6.405\ldots \) | ||
\(=6.41\) |
\(\Rightarrow D\)
What is the value of `(a + b)/(ab)` if `a = -2.1 and b = -3.6`, correct to 1 decimal place? (2 marks)
`-0.8`
`(a + b)/(ab)` | `= (-2.1 – 3.6)/(-2.1 xx -3.6)` |
`= (-5.7)/7.56` | |
`= -0.753…` | |
`= -0.8` |
If `S = V_0 (1 - r)^n`, find `S` given `V_0 = $42\ 000, r = 0.16 and n = 4`. (give your answer to the nearest cent) (2 marks)
`$20\ 910.60\ text{(to nearest cent)}`
`S` | `= V_0 (1 – r)^n` |
`= 42\ 000 (1 – 0.16)^4` | |
`= 42\ 000 (0.84)^4` | |
`= $20\ 910.597…` | |
`= $20\ 910.60\ \ text{(to nearest cent)}` |
It is given that `I = 3/2 MR^2`.
What is the value of `I` when `M = 26.55` and `R = 3.07`, correct to two decimal places?
A. `375.35`
B. `3246.08`
C. `9965.45`
D. `14\ 948.18`
`A`
`I` | `= 3/2 xx 26.55 xx (3.07)^2` |
`= 375.346…` |
`=> A`
If `A = P(1 + r)^n`, find `A` given `P = $300`, `r = 0.12` and `n = 3` (give your answer to the nearest cent). (2 marks)
`$421.48\ \ text{(nearest cent)}`
`A` | `= P(1 + r)^n` |
`= 300(1 + 0.12)^3` | |
`= 300(1.12)^3` | |
`= 421.478…` | |
`= $421.48\ \ text{(nearest cent)}` |
What is the value of `5a^2 - b`, if `a = −4` and `b = 3`. (2 marks)
`77`
`5a^2 − b` | `= 5(−4)^2 − 3` |
`= 5 xx 16 − 3` | |
`= 77` |
If `V = 4/3 pir^3`, what is the value of `V` when `r = 2`, correct to two decimal places?
`D`
`V = 4/3 pir^3`
`text(When)\ \ r = 2,`
`V` | `= 4/3 pi xx 2^3` |
`= 33.510\ …` |
`=> D`
What is the value of `(a-b)/4`, if `a = 240` and `b = 56`?
`B`
`(a-b)/4` | `= (240-56)/4` |
`= 46` |
`=> B`
If `K = Ft^3`, `F = 5` and `t = 0.715`, what is the value of `K` correct to three significant figures?
`D`
`K` | `= Ft^3` |
`= 5 xx (0.715)^3` | |
`= 1.8276…` | |
`= 1.83\ \ text{(3 sig figures)}` |
`=> D`
This shape is made up of a right-angled triangle and a regular hexagon.
The area of a regular hexagon can be estimated using the formula `A = 2.598H^2` where `H` is the side-length.
Calculate the total area of the shape using this formula. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`22.784\ text(cm²)`
`text(Area) = 2.598H^2`
`text(Using Pythagoras)`
`H^2` | `= 2^2 + 2^2` |
`= 8` | |
`H` | `= sqrt 8` |
`:.\ text(Area of hexagon)` | `= 2.598 xx (sqrt 8)^2` |
`= 20.784\ text(cm²)` |
`text(Area of triangle)` | `= 1/2 bh` |
`= 1/2 xx 2 xx 2` | |
`= 2\ text(cm²)` |
`:.\ text(Total Area)` | `= 20.784 + 2` |
`= 22.784\ text(cm²)` |
What is the value of `sqrt ( (x + 2y)/(8y) )` if `x = 5.6` and `y = 3.1`, correct to 2 decimal places?
`A`
`sqrt ( (x + 2y)/(8y) )` | `= sqrt ( (5.6 + (2 xx 3.1))/((8 xx 3.1)) )` |
`= sqrt (11.8/24.8)` | |
`= 0.6897…` |
`=> A`
If `M=-9`, what is the value of `(3M^2+5M)/6`
`C`
`(3M^2+5M)/6` | `=(3xx(–9)^2+5xx(–9))/6` |
`=((3xx81)-45)/6` | |
`=198/6` | |
`=33` |
`=> C`