50 times 30 is 1500 and 9 times 8 is 72 added is 1572
Answer:
The unknown number is 90
Step-by-step explanation:
This question requires a good understanding so as to interprets it well
And always ensure that all symbols used in representation are well stated so as to help the examiner or anyone who will mark it to understand better
So back to the question,let the unknown number be x
And two thirds of the unknown number is 2/3x
2/3x was decreased by 20 which can be written as 2/3x-20
And this decrease gives 40
That's,2/3x-20=40
Then go ahead to solve the question
Start by finding the LCM and the LCM is 3
2x-60/3=40
Cross multiply
2x-60=40×3
2x-60=120
Collect like terms by adding 60 to both sides
2x=180
Divide both sides by 2
x=90
Therefore the final answer is 90
Answer:
320
Step-by-step explanation:
5x4=20, 20x4=80, so that means the sequence is just multiplying by 4. 80x4=320, which is your answer.
Let's start by visualising this concept.
Number of grains on square:
1 2 4 8 16 ...
We can see that it starts to form a geometric sequence, with the common ratio being 2.
For the first question, we simply want the fifteenth term, so we just use the nth term geometric form:


Thus, there are 16, 384 grains on the fifteenth square.
The second question begs the same process, only this time, it's a summation. Using our sum to n terms of geometric sequence, we get:



Thus, there are 32, 767 total grains on the first 15 squares, and you should be able to work the rest from here.
Answer: 
Step-by-step explanation:
Let x be the average number of pounds Fido must loss.
Since, the initial weight of Fido is 35 pounds.
And, After losing the weight, the new weight of Fido in pounds = 28 pounds.
Then the time taken for losing the weight
= 
= 
According to the question, it must lose weight within 6 months,
Thus, 
Which is the required inequality to find the average number of pounds per month.
By solving it we, get, 