Question

1. Word Problems

a)Subtract the sum of the predecessor of the largest 4 -digit number and the successor of the least two digit number from th sum of the predecessor of the largest 7-digit number and the successor of the lease 3-digit number .

b) three bells toll ar intervals of 12,16,24 minutes . If they begin to toll toghether at 8 am, at what time will thhey toll toghether

Answer 1

Answer :

1 ) We know largest 7 digit number = 9999999
And predecessor of that number = 9999998
We know least 3 digit number = 100
And successor of that number = 101
And sum of these numbers = 9999998 + 101 = 10000099

And
We know largest 4 digit number = 9999
And predecessor of that number = 9998
we know least 2 digit number = 10
And successor of that number = 11
Sum of these two numbers = 9998 + 11 = 10009

Now we subtract them = 10000099 - 10009 = ​9990090 ( Ans )

2 ) given : ​Three bells toll at intervals of 12,16,24 minutes
So to find out at what time they will toll together as they toll at 8 am ,

we find L.C.M. of these given time interval As :

So LCM of these numbers = 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 3 = 48

SO,

Next time three bells toll together at 8 : 48 am ( Ans )