East Level 2
Well-Known Member
2, 17 and 19A, b, and c are three prime numbers such that a×b×c= 17x(a+b+c). What is the value of a, b and c?
2, 17 and 19A, b, and c are three prime numbers such that a×b×c= 17x(a+b+c). What is the value of a, b and c?
Yup. I like to set these problems for my son, who is in Y2 Maths at MMU. This one took him five minutes.2, 17 and 19
Isn't the 8 missing?Get kids to put 99999999.9 into their calculator and divide by 3 to get 33333333.3. Divide by 3 again and get 11111111.1. Divide once more and you get a random number but divide that by 3 and you get 12345678.9
They think its magic.
(I hope l got the right number of digits each time. I am going sken eyed trying to count them.
L
.
It was obvious one of the numbers was 17 and comparing two tables, 17*(17+a+b) and 17*a*b, in Excel did the rest.Yup. I like to set these problems for my son, who is in Y2 Maths at MMU. This one took him five minutes.
Was doing it from memory as I didnt have a calculator to hand to confirm but i think it was done by pressing all the nines on a standard calculator until the display was full and doing the division from there. Some calculators were different because of the way they rounded up digits at the end.Isn't the 8 missing?
You can use any fingers you want.Can someone tell what digits you need to put boobless into the calculator?