Question
Two different dice are thrown together. Find the probability that the numbers obtained:
  1. Have a sum less than $7.$
  2. Have a product less than $16.$
  3. Is a doublet of odd numbers.

Answer

The outcomes when two dice are thrown together are:
$(1, 1), (1, 2), (2, 3), (1, 4), (1, 5), (1, 6)$
$(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6)$
$(3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6)$
$(4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6)$
$(5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6)$
$(6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)$
  1. Let A be the event of getting the number whose sum is less than 7.
The outcomes in favour of event A are: $(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (2, 1), (2, 2), (2, 3), (2, 4), (3, 1), (3, 2), (3, 3), (4, 1), (4, 2)$ and $(5, 1)$
Number of favourable outcones $= 15$
$\therefore\ \text{P(A)}=\frac{\text{Number of favourable outcomes}}{\text{Total number of outcomes}}$
$=\frac{15}{36}$
$=\frac{5}{12}$
  1. Let B be the event of getting the number whose product is less than $16.$
The outcomes in favour of event $B$ are: $(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 1), (2, 2), (2, 3), (2, 4),$
$ (2, 5), (2, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (4, 1), (4, 2), (4, 3), (5, 1), (5, 2), (5, 3), (6, 1)$ and $(6, 2).$
  1. Let $C$ be the event of getting the number which are doublets of odd numbers
The outcomes in favour of event $C$ are $(1, 1), (3, 3)$ and $(5, 5)$
Number of favourable outcomes $= 3$
$\therefore\ \text{P(A)}=\frac{\text{Number of favourable outcomes}}{\text{Total number of outcomes}}$
$=\frac{3}{36}$
$=\frac{1}{12}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Obtain all zeros of the polynomial $f(x)=2 x^4+x^3-14 x^2-19 x-6$, if two of its zeros are $-2$ and $-1.$
Three numbers are in $A.P$. If the sum of these numbers be $27$ and the product $648$, find the numbers.
In a potato race, a bucket is placed at the starting point, which is $5\ m$ from the first potato, and the other potatoes are placed $3\ m$ apart in a straight line. There are $10$ potatoes in the line. A competitor starts from the bucket, picks up the nearest potato, runs back with it, drops it in the bucket, runs back to pick up the next potato to the bucket to drop it in, and he continues in the same way until all the potatoes are in the bucket. What is the total distance the competitor has to run?
A two-digit number is $4$ times the sum of its digits. If $18$ is added to the number, the digits are reversed. Find the number.
Solve the following quadratic equations by factorization:
$\frac{5+\text{x}}{5-\text{x}}-\frac{5-\text{x}}{5+\text{x}}=3\frac{3}{4},$ $\text{x}\neq5,-5$
To fill a swimming pool two pipes are used. If the pipe of larger diameter used for $4$ hours and the pipe of smaller diameter for $9$ hours, only half of the pool can be filled. Find, how long it would take for each pipe to fill the pool separately, if the pipe of smaller diameter takes $10$ hours more than the pipe of larger diameter to fill the pool?
The points $A(2, 0), B(9, 1) C(11, 6)$ and $D(4, 4)$ are the vertices of a quadrilateral $ABCD$. Determine whether $ABCD$ is a rhombus or not.
To find out the concentration of $S0_2$ in the air $($in parts per million, i.e., ppm$),$ the data was collected for $30$ localities in a certain city and is presented below:
Concentration of $SO_2 ($in ppm$)$ Frequency
$0.00-0.04$ $4$
$0.04-0.08$ $9$
$0.08-0.12$ $9$
$0.12-0.16$ $2$
$0.16-0.20$ $4$
$0.20-0.24$ $2$
Find the mean concentration of $SO_2$ in the air.
Solve the following quadratic equations by factorization:
$3\Big(\frac{7\text{x}+1}{5\text{x}-3}\Big)-4\Big(\frac{5\text{x}-3}{7\text{x}+1}\Big)=11,$ $\text{x}\neq\frac{3}{5},-\frac{1}{7}$
A metallic cylinder has radius $3\ cm$ and height $5\ cm$. To reuce its weight, a conical hole is drilled in the cylinder. The conical hole has a radius of $\frac{3}{2}\text{cm}$ and its depth is $\frac{8}{9}\text{cm}.$ Calculate the ratio of the volume of metal left in the cylinder to the volume of metal taken out in conical shape.