# F.1 Maths Questions

1. 150 balls are put into two boxes A andB. If the number of balls in

box B is a nultiple of that in box A ,suggest two pairs of the numbers

balls in boxes A and B.

2. Jenny wants to send a parcel to her uncle. The postage is \$38.2.She has

some \$1.4-stamps, \$2.5-stamps. Suggest two ways paying the postage

using these kinds of stamps.

Rating

1. 150balls are put into two boxes A and B. If the number of balls in box B is a multipleof that in box A , suggest two pairs of the numbers balls in boxes A and B.Factors of 150 : 1,2, 3, 5, 6, 10, 15, 25, 30, 75, 150

1x150, 2x75,3x50,5x30, 6x25, 10x15, 15x10, 2x6, 30x5, 50x3, 75x2, 150x1

If A = 1, B = 2x(150-1),

A+B

= 1+1x(150-1)

= 1+1x149

=1+149

=150

If A = 2, B = 2x(75-1),

A+B

= 2+2x(75-1)

= 2+2x74

=2+148

=150

……

2. Jennywants to send a parcel to her uncle. The postage is \$38.2.She has some\$1.4-stamps, \$2.5-stamps. Suggest two ways paying the postage using these kindsof stamps.

1.4x13 + 2.5x8

= 18.2+20

=38.2

2008-08-06 16:21:27 補充：

1x150, 2x75,3x50,5x30, 6x25, 10x15

Source(s): myself
• 1. 10,140 or 50, 100

2. thirteen \$1.4 stamps and eight \$2.5 stamps (=\$38.2, the only solution that can give 38.2)

or three \$2.5 stamps and 22 \$1.4 stamps (this will give \$38.3)