Frequently Asked Questions
A two digit number is 4 times the sum of its digits and twice
the product of its digits.The number is - - - - - -
Solution:
Explanation:
Let x be the digit in the ones place and y be the digit in the tens place, resulting in the two-digit number = 10 y + x..
Given that the sum of the digits of a two-digit integer equals four,
According to the question
,
Final Answer:
The number is 36.
The angle of elevation of the top of a tower from a point on the ground
which is 30m away from the foot of the tower, is 30∘. Find the height of the tower.
Solution:
Explanation:
Let us take the height of the tower to be AB
Let C be the point elevation which is 30m away from the foot of the tower
We know that for a given right angled triangle,
Final Answer:
The height of the tower : 10 Root 3m
Prove that the product of three consecutive positive integers is divisible by 6
Solution:
Explanation:
Let us take the three consecutive positive integers as : a,a + 1,a + 2
A number when divided by 3, will have a remainder = 0 or 1 or 2
We can clearly see the numbers a,a + 1,a + 2 are always divisible by 3.
Similarly, we can show that when a number is divisible by 2, we get the remainder as 0 or 1
Clearly, 2m and 2(m+1) both are divisible by 2.
We can clearly see the numbers a,a + 1,a + 2 are always divisible by 2.
We can say that a,a + 1,a + 2 is always divisible by 2 ,3 ,6
Example:
Let us take: 3,4,5
3 x 4 x 5 = 60
We can see that 60 is divisible by 6