Congruent triangles have the exact same three sides and the exact same angles. They are identical. So if you look at your triangles carefully, they are congruent. :)
Length of blue cloth is 60 inches , length of gold cloth is 48 inches and length of white cloth is 72 inches.
<u>a.</u>
As, the length of all pieces are equal, so for getting the greatest possible length of the pieces, we need to find <u>GCF(greatest common factor) of 60, 48 and 72. </u>
First we will factor out all three numbers completely......

The common factors are: 2, 2 and 3
Thus the GCF 
So, the greatest possible length of the pieces without having any cloth left over will be 12 inches.
<u>b. </u>
For finding the number of pieces for each color cloth, we will just <u>divide the length of each cloth by 12</u>. So...
Number of pieces for blue cloth 
Number of pieces for gold cloth
and
Number of pieces for white cloth 
56 + 90 = 146 kilometers
4 + 2 = 6 hours
rate = 146 km / 6 hour
= 24.333 km / hour
99 and 59
X=big number
X-40 = small
X+ x-40 =158
2X -40=158
2X =198
X=99. Big number is 99
99-40 =59
99+59=158